integral of 3x^2 is (9/3)x^3 + c
I can't see option d but none of the others look correct.
Help!!!!!! Please!!!!
Answer: 30u
Step-by-step explanation:
If GY is 6u long, x=6. (4x-2) is 4x6 which is 32, 32 - 2 = 30u long
(U = units)
Graphic DesignWorks ships the T-shirts it makes in boxes that measure 24 in
x 18 in x 16 in. The company rents a storage space that measures 400 ft x
240 ft x 60 ft. What is the best estimate of the number of boxes Graphic
DesignWorks is able to store?
A. 576,000 boxes
B. 1,440,000 boxes
C. 6912 boxes
D. 972,000 boxes
Answer:The answer is c
Step-by-step explanation:
The best estimate of the number of boxes Graphic DesignWorks is able to store is 1440000 boxes.
What is volume?
Volume is the three-dimensional space enclosed by a three-dimensional object.
We have to find the volume of the box and the volume of the storage space.
The volume of the box:Volume = length × breadth × height
= 24 × 18× 16 in³
=6912 in³
The volume of the storage space:Volume = length × breadth × height
= 400 × 240 × 60 ft³
= 5760000 ft³
We have to convert this into inches. We know that 1 foot = 12 inches.Therefore, 5760000 ft³ = 5760000 × (12)³ in³
We have to divide the volume of the storage space by the volume of the box to find the number of boxes that it can fit:Number of boxes that can fit inside the storage space = (5760000 × (12)³ in³)/6912 in³
= 1440000 boxes.
Thus, the best estimate of the number of boxes Graphic DesignWorks is able to store is 1440000 boxes. The correct answer is option B.
Learn more about volume here-https://brainly.com/question/25736513
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find the measure of each angle indicated
Answer:
D) 111
Step-by-step explanation:
Internal Alternate angle thm states 111 and x are equal:
? = 111
Answer:
D
Step-by-step explanation:
its the same as the angle that was given to you
what is the slope of (4,7) (9,7)?! please help i tried omni and it didn't give me an answer
Answer:
0
Step-by-step explanation:
1. Find the factor pairs of the following number: 54
Answer:
1, 2, 3, 6, 9, 18, 27, 54.
Step-by-step explanation:
factors:
1, 2, 3, 6, 9, 18, 27, 54.
Therefore, all the factor pairs for 54 is 1, 2, 3, 6, 9, 18, 27, 54..
Answer: (1,54) (2,27) (3,18) (6,9)
Step-by-step explanation: 54 x 1 = 54 27 x 2 = 54 3 x 18 = 54 6 x 9 = 54
PLEASE HELP! Which of the following teams will have a greater standard deviation in their heights ?
What is the average rate of change for f(x) = 2X – 12 over the interval 4sxs8?
A)
10
B)
30
60
D
90
Answer:
Step-by-step explanation:
I think its B, (30)
A certain type of aluminum screen has, an average, one flaw in a 100-foot roll. Assume the flaw distribution approximately follows the Poisson distribution. (a) Find the probability that a 100-foor roll has at most 2 flaws. (b) Suppose that I bought 10 200-foot rolls, find the probability that there are exactly 3 rolls that have no flaws in them. (c) Suppose that a store had many 200-foot rolls in storage, a clerk is doing inspections. What is the probability that the 15th roll he inspected was the 3rd one that have no flaws in it
Answer:
a) 0.9197 = 91.97% probability that a 100-foor roll has at most 2 flaws.
b) 0.1074 = 10.74% probability that there are exactly 3 rolls that have no flaws in them.
c) 0.0394 = 3.94% probability that the 15th roll he inspected was the 3rd one that have no flaws in it.
Step-by-step explanation:
To solve this question, we need to understand the Poisson and the Binomial distribution.
Poisson distribution:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\mu[/tex] is the mean in the given interval.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
(a) Find the probability that a 100-foor roll has at most 2 flaws.
A certain type of aluminum screen has, an average, one flaw in a 100-foot roll, which means that [tex]\mu = 1[/tex]. Only one roll means that the Poisson distribution is used.
This is:
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2)[/tex]
In which
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 0) = \frac{e^{-1}*1^{0}}{(0)!} = 0.3679[/tex]
[tex]P(X = 1) = \frac{e^{-1}*1^{1}}{(1)!} = 0.3679[/tex]
[tex]P(X = 2) = \frac{e^{-1}*1^{2}}{(2)!} = 0.1839[/tex]
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) = 0.3679 + 0.3679 + 0.1839 = 0.9197[/tex]
0.9197 = 91.97% probability that a 100-foor roll has at most 2 flaws.
(b) Suppose that I bought 10 200-foot rolls, find the probability that there are exactly 3 rolls that have no flaws in them.
Two parts.
Probability that a single 200-foot roll has no flaw.
This is [tex]P(X = 0)[/tex], Poisson(single 200-foot roll) when [tex]\mu = \frac{200*1}{100} = 2[/tex]. So
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 0) = \frac{e^{-2}*2^{0}}{(0)!} = 0.1353[/tex]
0.1353 probability that a single 200-foot roll has no flaw.
Probability that on 10 200-foot rolls, 3 have no flaws.
Multiple 200-foot rolls means that we use the binomial distribution.
0.1353 probability that a single 200-foot roll has no flaw means that [tex]p = 0.1353[/tex]
10 200-foot rolls means that [tex]n = 10[/tex]
We want [tex]P(X = 3)[/tex]. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 3) = C_{10,3}.(0.1353)^{3}.(0.8647)^{7} = 0.1074[/tex]
0.1074 = 10.74% probability that there are exactly 3 rolls that have no flaws in them.
(c) What is the probability that the 15th roll he inspected was the 3rd one that have no flaws in it.
0.1353 probability that a single 200-foot roll has no flaw means that [tex]p = 0.1353[/tex]
2 with flaws in the first 14, which is [tex]P(X = 2)[/tex] when [tex]n = 14[/tex]
The 15th has no flaw, with probability of 0.1353. So
[tex]P = 0.1353*P(X = 2) = 0.1353*(C_{14,2}.(0.1353)^{2}.(0.8647)^{12}) = 0.1353*0.2911 = 0.0394[/tex]
0.0394 = 3.94% probability that the 15th roll he inspected was the 3rd one that have no flaws in it
Pls help it's due tonight!!!
:((((((
Answer:
∆EDA~∆ECB (AAA)
3÷ (15+3) = AB ÷ (12+AB)
AB = 2.4
What is the perimeter of square ABCD?
This is how you do it.
Use the distance formula to find the distance from A to B, B to C, C to D and D to A. Then add up all 4 distances to find the perimeter.
pls help me asapp quick easy 10 points
Please help me!! I’m really bad at math
5m=105 what is m in the equation
Answer:
m = 21
Step-by-step explanation:
5m = 105
5m ÷ 5 = 105 ÷ 5
m = 21
How many solutions ?
Answer:
one solution
the solution is x=0
Answer:
1
Step-by-step explanation:
You can figure this out using a simple trick. The highest number to the power that a variable goes to is the number of answers for that question. Meaning if There was an x cubed in that problem, there would be 3 answers.
When a button is pressed, a computer program outputs a random odd number greater than 1 and less than 9. You press the button 4 times. How many possible outcomes are there?
Answer:
Well if it is 1 to 9 and you press it 4 times you will have 9 possible outcomes
Step-by-step explanation:
The number of possible outcomes when the button is pressed 4 times is; 81 outcomes
Number of possible outcomesWhen the button is pressed first, the possible choices of random odd number are; 3, 5 and 7.This is because the sample space includes odd numbers between 1 and 9 excluding 1 and 9.
Since number of possible choices for one press is 3,then for four presses, we will have;
3⁴ = 81 possible outcomes
Read more on probability outcomes at; https://brainly.com/question/25376712
The vector matrix [-3,-5] is rotated at different angles. Match the angles of rotation to the vector matrices they produce.
Answer: The above answer is correct.
Step-by-step explanation: I got this correct on Edmentum.
Answers
[tex]A' = \left[\begin{array}{cc}5.830\\-0.098\end{array}\right][/tex], [tex]\theta = \frac{2\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}-5.657\\-1.414\end{array}\right][/tex], [tex]\theta = \frac{7\pi}{4}[/tex]
[tex]A' = \left[\begin{array}{cc}-2.83\\5.098\end{array}\right][/tex], [tex]\theta = \frac{4\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}5\\-3\end{array}\right][/tex], [tex]\theta = \frac{\pi}{2}[/tex]
This exercise consist in finding the resulting Vector Matrix for each Angle of Rotation and a given Vector Matrix. The result is found by multiplying the given Vector Matrix for a Rotation Matrix, defined below as follows:
[tex]A' = R\cdot A[/tex] (1)
Where:
[tex]A[/tex] - Given vector matrix.
[tex]R[/tex] - Rotation matrix.
[tex]A'[/tex] - Resulting vector matrix.
For 2-dimension Vector Matrices, The Rotation Matrix is defined by the following entity:
[tex]R = \left[\begin{array}{cc}\cos \theta&-\sin \theta\\\sin \theta&\cos \theta\\\end{array}\right][/tex] (2)
Where [tex]\theta[/tex] is the Angle of Rotation, in radians.
Let be [tex]A = \left[\begin{array}{cc}x\\y\end{array}\right][/tex], the resulting vector matrix is found by (1) and (2):
[tex]A' = \left[\begin{array}{cc}\cos \theta&-\sin \theta\\\sin \theta&\cos \theta\end{array}\right] \cdot \left[\begin{array}{cc}x\\y\end{array}\right][/tex]
[tex]A' = \left[\begin{array}{cc}x\cdot \cos \theta - y\cdot \sin \theta\\x\cdot \sin \theta +y\cdot \cos \theta \end{array}\right][/tex]
If we know that [tex]A = \left[\begin{array}{cc}-3\\-5\end{array}\right][/tex], then the resulting vector matrix for each angle is, respectively:
[tex]\theta = \frac{\pi}{4}[/tex]
[tex]A' = \left[\begin{array}{cc}1.414\\-5.657\end{array}\right][/tex]
[tex]\theta = \frac{\pi}{2}[/tex]
[tex]A' = \left[\begin{array}{cc}5\\-3\end{array}\right][/tex]
[tex]\theta = \frac{2\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}5.830\\-0.098\end{array}\right][/tex]
[tex]\theta = \frac{4\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}-2.83\\5.098\end{array}\right][/tex]
[tex]\theta = \frac{5\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}-5.83\\0.098\end{array}\right][/tex]
[tex]\theta = \frac{7\pi}{4}[/tex]
[tex]A' = \left[\begin{array}{cc}-5.657\\-1.414\end{array}\right][/tex]
Therefore, we have the following answers:
[tex]A' = \left[\begin{array}{cc}5.830\\-0.098\end{array}\right][/tex], [tex]\theta = \frac{2\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}-5.657\\-1.414\end{array}\right][/tex], [tex]\theta = \frac{7\pi}{4}[/tex]
[tex]A' = \left[\begin{array}{cc}-2.83\\5.098\end{array}\right][/tex], [tex]\theta = \frac{4\pi}{3}[/tex]
[tex]A' = \left[\begin{array}{cc}5\\-3\end{array}\right][/tex], [tex]\theta = \frac{\pi}{2}[/tex]
Related question: https://brainly.com/question/11815899
What is the range of the following exponential function?plz help asap
Answer:
0.23
Step-by-step explanation:
Solve for x. Leave your answer in simplest radical form
Answer:
x = sqrt(39)
Step-by-step explanation:
Let y = common side of the two triangles.
Upper right triangle:
6^2 + y^2 = 10^2
y^2 = 100 - 36
y^2 = 64
y = 8
Lower left triangle:
5^2 + x^2 = 8^2
x^2 = 64 - 25
x^2 = 39
x = sqrt(39)
... Helppppp!! will mark brainiest
Answer: The answer is C
Step-by-step explanation:
C is the answer because the base is +2 and the coefficent is 1/2 which is rise over run so you go up one space and to the right two spaces.
g In a random sample of 60 shoppers chosen from the shoppers at a large suburban mall, 36 indicated that they had been to a movie in the past month. In an independent random sample of 50 shoppers chosen from the shoppers in a large downtown shopping area, 31 indicated that they had been to a movie in the past month. What significance test should be used to determine whether these data provide sufficient evidence to reject the hypothesis that the proportion of shoppers at the suburban mall who had been to a movie in the past month is the same as the proportion of shoppers in the large downtown shopping area who had been to a movie in the past month
Answer:
Option E, two-proportion z test should be used to determine whether these data provide sufficient evidence to reject the hypothesis that the proportion of shoppers at the suburban mall who had been to a movie in the past month is the same as the proportion of shoppers in the large downtown shopping area who had been to a movie in the past month
Step-by-step explanation:
The complete question is
In a random sample of 60 shoppers chosen from the shoppers at a large suburban mall, 36 indicated that they had been to a movie in the past
month. In an independent random sample of 50 shoppers chosen from the shoppers in a large downtown shopping area, 31 indicated that
they had been to a movie in the past month. What significance test should be used to determine whether these data provide sufficient
evidence to reject the hypothesis that the proportion of shoppers at the suburban mall who had been to a movie in the past month is the same
as the proportion of shoppers in a large downtown shopping area who had been to a movie in the past month?
A one-proportion z interval B two-proportion z interval
B two-proportion z interval
C two-sample t test D one-proportion z test
D one-proportion z test
E two-proportion z test
Solution
Two proportion z test is used to compare two proportions. In this test the null hypothesis is that the two proportions are equal and the alternate hypothesis is that the proportions are not the same. The random sample of populations serve as two proportions.
Hence, option E is the best choice of answer
A small jar of peanut butter sells for 0.08 per ounce. A large jar of peanut butter sells for $1.20 per pound. Which is the better buy and by how much (in cents per pound)?
Answer:
a small jar of penuts buteer sells for 0.08 per ounce
A large jar of penut buttter sells for $1.20 per pound
the answer is :
hope it will help you
Add: look at the picture
Answer:
5 3/4
Step-by-step explanation:
the 3/4 is a fraction
Have a nice day:)
Answer:
5 3/4
Step-by-step explanation:
2 + 2/3 + 3 + 1/12
2+3= 5
2/3 + 1/12 <<-- Find the LCD
8/12 + 1/12 = 9/12 <-- Reduce the fraction
9/12 = 3/4
5 + 3/4 = 5 3/4
Diane sells candles online and ships them to her customers. Each candle weighs 1.5 pounds. When a customer orders more than one candle, Diane ships all of the customer's candles in one box. She weighs the box to determine shipping cost. This table shows the weight per shipment. Choose ALL amounts that could be added to this table. A) 4.5 B) 5 C) 6 D) 6.5 E) 7
Answer:Its b
Step-by-step explanation:
I will venmo if someone can please help me
Answer: 14.967
Step-by-step explanation:
Use Pythagorean Theorem to find the missing length.
a² + b² = c²
x² + 10² = 18²
x² + 100 = 324 [Subtract 100 from both side]
x²= 224
√x² = √224 [solve the square root from both sides]
x ≈ 14.967
find the area of the shaded region. geometry please help if your good at it. will mark brainlist
Area of shaded region = area of circle - area of segment
(where "segment" refers to the unshaded region)
Area of circle = π (11.1 m)² ≈ 387.08 m²
The area of the segment is equal to the area of the sector that contains it, less the area of an isosceles triangle:
Area of segment = area of sector - area of triangle
130° is 13/36 of a full revolution of 360°. This is to say, the area of the sector with the central angle of 130° has a total area equal to 13/36 of the total area of the circle, so
Area of sector = 13/36 π (11.1 m)² ≈ 139.78 m²
Use the law of cosines to find the length of the chord (the unknown side of the triangle, call it x) :
x ² = (11.1 m)² + (11.1 m)² - 2 (11.1 m)² cos(130°)
x ² ≈ 404.82 m²
x = 20.12 m
Call this length the base of the triangle. Use a trigonometric relation to determine the corresponding altitude/height, call it y. With a vertex angle of 130°, the two congruent base angles of the triangle each measure (180° - 130°)/2 = 25°, so
sin(25°) = y / (11.1 m)
y = (11.1 m) sin(25°)
y ≈ 4.69 m
Then
Area of triangle = xy/2 ≈ 1/2 (20.12 m) (4.69 m) ≈ 47.19 m²
so that
Area of segment ≈ 139.78 m² - 47.19 m² ≈ 92.59 m²
Finally,
Area of shaded region ≈ 387.08 m² - 92.59 m² ≈ 294.49 m²
PLEASE HELP!!!!!! ILL GIVE BRAINLIEST *EXTRA 40 POINTS** !! DONT SKIP :((
A recipe uses 3 eggs to make 2 dozen cookies. There are 12 cookies in 1 dozen. How many eggs are used to make 6 dozen cookies? A.3 B.6 C.9 D.12 please help it would mean a lot <3
Answer:
C.9
Step-by-step explanation:
2 doz =3eggs
4 doz = 6 eggs
6 doz = 9 eggs
Help please
And thank you
Answer:
Step-by-step explanation:
The lifetime of battery of a device (in one charge) is normally distributed with mean µ = 18 hours and standard deviation σ = 2 hours. (a) What is the probability that a battery will last more than 20 hours? (b) Find the 10th percentile of the lifetimes. (c) A particular battery lasts 16 hours. What percentile is its lifetime on? (d) What is the probability that the lifetime of a battery is between 17.5 and 18.5? (e) Ten batteries are chosen at random, what is the probability that the mean lifetime is between 17.5 and 18.5?
Answer:
a) 0.1587 = 15.87% probability that a battery will last more than 20 hours.
b) 15.44 hours.
c) Approximately the 16th percentile.
d) 0.1974 = 19.74% probability that the lifetime of a battery is between 17.5 and 18.5.
e) 0.5704 = 57.04% probability that the mean lifetime is between 17.5 and 18.5
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
In this question, we have that:
[tex]\mu = 18, \sigma = 2[/tex]
(a) What is the probability that a battery will last more than 20 hours?
This is 1 subtracted by the pvalue of Z when X = 20. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{20 - 18}{2}[/tex]
[tex]Z = 1[/tex]
[tex]Z = 1[/tex] has a pvalue of 0.8413
1 - 0.8413 = 0.1587
0.1587 = 15.87% probability that a battery will last more than 20 hours.
(b) Find the 10th percentile of the lifetimes.
This is X when Z has a pvalue of 0.1. So X when Z = -1.28
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.28 = \frac{X - 18}{2}[/tex]
[tex]X - 18 = -1.28*2[/tex]
[tex]X = 15.44[/tex]
So 15.44 hours.
(c) A particular battery lasts 16 hours. What percentile is its lifetime on?
We have to find the pvalue of Z when X = 16. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{16 - 18}{2}[/tex]
[tex]Z = -1[/tex]
[tex]Z = -1[/tex] has a pvalue of 0.1587
Approximately the 16th percentile.
(d) What is the probability that the lifetime of a battery is between 17.5 and 18.5?
This is the pvalue of Z when X = 18.5 subtracted by the pvalue of Z when X = 17.5. So
X = 18.5
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{18.5 - 18}{2}[/tex]
[tex]Z = 0.25[/tex]
[tex]Z = 0.25[/tex] has a pvalue of 0.5987
X = 17.5
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{17.5 - 18}{2}[/tex]
[tex]Z = -0.25[/tex]
[tex]Z = -0.25[/tex] has a pvalue of 0.4013
0.5987 - 0.4013 = 0.1974
0.1974 = 19.74% probability that the lifetime of a battery is between 17.5 and 18.5.
(e) Ten batteries are chosen at random, what is the probability that the mean lifetime is between 17.5 and 18.5?
Sample of 10 means that, by the Central Limit Theorem, [tex]n = 10, s = \frac{2}{\sqrt{10}} = 0.6325[/tex]
X = 18.5
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{18.5 - 18}{0.6325}[/tex]
[tex]Z = 0.79[/tex]
[tex]Z = 0.79[/tex] has a pvalue of 0.7852
X = 17.5
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{17.5 - 18}{0.6325}[/tex]
[tex]Z = -0.79[/tex]
[tex]Z = -0.79[/tex] has a pvalue of 0.2148
0.7852 - 0.2148 = 0.5704
0.5704 = 57.04% probability that the mean lifetime is between 17.5 and 18.5
Wright et al. [A-2] used the 1999-2000 National Health and Nutrition Examination Survey(NHANES) to estimate dietary intake of 10 key nutrients. One of those nutrients was calcium (mg). They found in all adults 60 years or older a mean daily calcium intake of 721 mg with a standard deviation of 454. Using these values for the mean and standard deviation for the U.S. population, find and interpret the probability that a random sample of size 50 will a mean:
Complete question :
Wright et al. [A-2] used the 1999-2000 National Health and Nutrition Examination Survey NHANES) to estimate dietary intake of 10 key nutrients. One of those nutrients was calcium in all adults 60 years or older a mean daily calcium intake of 721 mg with a standard deviation of 454. Usin these values for the mean and standard deviation for the U.S. population, find the probability that a randonm sample of size 50 will have a mean: (mg). They found a) Greater than 800 mg b) Less than 700 mg. c) Between 700 and 850 mg.
Answer:
0.10935
0.3718
0.9778
0.606
Step-by-step explanation:
μ = 721 ; σ = 454 ; n = 50
P(x > 800)
Zscore = (x - μ) / σ/sqrt(n)
P(x > 800) = (800 - 721) ÷ 454/sqrt(50)
P(x > 800) = 79 / 64.205295
P(x > 800) = 1.23
P(Z > 1.23) = 0.10935
2.)
Less than 700
P(x < 700) = (700 - 721) ÷ 454/sqrt(50)
P(x < 700) = - 21/ 64.205295
P(x < 700) = - 0.327
P(Z < - 0.327) = 0.3718
Between 700 and 850
P(x < 850) = (850 - 721) ÷ 454/sqrt(50)
P(x < 850) = 129/ 64.205295
P(x < 700) = 2.01
P(Z < 2.01) = 0.9778
P(x < 850) - P(x < 700) =
P(Z < 2.01) - P(Z < - 0.327)
0.9778 - 0.3718
= 0.606