Answer:
a) the probability of (2 < X < 6) is 0.6247
b) the value of c is 3.878
c) the value of E[ x² ] is 13
Step-by-step explanation:
Given that;
mean μ = 3
variance = 4
standard deviation s = √variance = √4 = 2
(a) Find the probability P(2 < X < 6)
P(2 < X < 6) = p( (x - μ / s ) < z < (x - μ / s ) )
= p( (2 - 3 / 2 ) < z < (6 - 3 / 2 ) )
= p( -0.5 < z < 1.5)
from z-score table, 1.5; z = 0.9332 and -0.5; z = 0.3085
so
P(2 < X < 6) = 0.9332 - 0.3085 = 0.6247
Therefore, the probability of (2 < X < 6) is 0.6247
b) Find the value c such that P(X > c) = 0.33
with p-value = 0.33, the corresponding z -score to the right is 0.439
we know that;
z = x - μ / s
we substitute
0.439 = x - 3 / 2
x - 3 = 2 × 0.439
x - 3 = 0.878
x = 0.878 + 3
x = 3.878
Therefore, the value of c is 3.878
c) Find E[ x² ].
Variance = E[ x² ] - [ mean ]²
E[ x² ] = Variance + [ mean ]²
we substitute
E[ x² ] = 4 + [ 3 ]²
E[ x² ] = 4 + 9
E[ x² ] = 13
Therefore, the value of E[ x² ] is 13
The distribution follows a normal distribution.
[tex]\mathbf{P(2 < x < 6) =0.6247}[/tex]The value of c is 3.878The value of [tex]\mathbf{E(x^2) }[/tex] is 13The given parameters are:
[tex]\mathbf{\mu = 3}[/tex] --- mean
[tex]\mathbf{\sigma^2= 4}[/tex] --- variance
(a) P(2 < x < 6)
Start by calculating the standard deviation
[tex]\mathbf{\sigma = \sqrt{\sigma^2}}[/tex]
This gives
[tex]\mathbf{\sigma = \sqrt{4}}[/tex]
[tex]\mathbf{\sigma =2}[/tex]
Calculate the z-scores for x = 2 and 6
[tex]\mathbf{z = \frac{x - \mu}{\sigma}}[/tex]
So, we have:
[tex]\mathbf{z = \frac{2 - 3}{2} = -0.5}[/tex]
[tex]\mathbf{z = \frac{6 - 3}{2} = 1.5}[/tex]
So, the probability becomes
[tex]\mathbf{P(2 < x < 6) = P(-0.5 < z < 1.5)}[/tex]
Using z table of probabilities, we have:
[tex]\mathbf{P(2 < x < 6) =0.9332 - 0.3085}[/tex]
[tex]\mathbf{P(2 < x < 6) =0.6247}[/tex]
(b) Calculate c if P(X > c) = 0.33
Start by calculating the z-score for p-value = 0.33
From the z table, z = 0.439 when p-value = 0.33
Recall that:
[tex]\mathbf{z = \frac{x - \mu}{\sigma}}[/tex]
So, we have:
[tex]\mathbf{0.439 = \frac{x - 3}{2}}[/tex]
Multiply both sides by 2
[tex]\mathbf{0.878= x - 3}[/tex]
Add 3 to both sides
[tex]\mathbf{3.878= x}[/tex]
Rewrite as:
[tex]\mathbf{x = 3.878}[/tex]
Replace x with c
[tex]\mathbf{c = 3.878}[/tex]
The value of c is 3.878
(c) Calculate E[x²]
The variance of a dataset is:
[tex]\mathbf{\sigma^2 =E(x^2) - \mu^2}[/tex]
Substitute known values
[tex]\mathbf{4 =E(x^2) - 3^2}[/tex]
[tex]\mathbf{4 =E(x^2) - 9}[/tex]
Add 9 to both sides
[tex]\mathbf{13 =E(x^2) }[/tex]
Rewrite as:
[tex]\mathbf{E(x^2) = 13 }[/tex]
Hence, the value of [tex]\mathbf{E(x^2) }[/tex] is 13
Read more about normal random variables at:
https://brainly.com/question/11395972
On Monday Mrs. Wise bought 3 lbs of apples at $4 per lb. On Tuesday, apples were on sale for 20% off so she bought another 5 lbs. What was the price of apples on Monday?
Answer:
$12 on Monday
$16 on Tuesday
$28 in total
Step-by-step explanation:
Multiply the number of pounds by the cost per pound on Monday:
3 * 4 = $12 on Monday
If you want to find the price on Tuesday as well (I know it doesn't ask for it) you can calculate 20% of 4 by multiplying:
4 * 0.2 = 0.80
Next, subtract the 20% from the normal price:
4 = 0.80 = 3.20
Finally, multiply the discounted price by the number of pounds she bought:
3.20 * 5 = $16 on Tuesday
You can find the total of both Monday and Tuesday by adding the two together:
12 + 16 = $28.00 in total
Can someone help me with this? I literally cant think today. ;-; Thanks if you answer it correctly. ಥ‿ಥ
Answer:
The slope is 300
Step-by-step explanation:
Rise over run we see two points how many times do we rise and run to get there?
(Slope= rise/run)
So you rise 300 times (Since half of 600 is 300) then you run 1 time which is 300/1 which is 300
Find the area of a triangle where the base is 3 3/4 in and the height is 4 inches.
Helpppppp Asapppp guys
Answer:
[tex]-20\frac{3}{4}[/tex] < [tex]-15\frac{1}{2}[/tex] < [tex]-14\frac{3}{4}[/tex] < [tex]-\frac{1}{4}[/tex]
Step-by-step explanation:
Just so you know, the larger a negative number is, the smaller the number's value is.
Can anyone help with 11-15?
Answer:
11. 1/3
12. 2/5
13. 1/4
14. 1/5
15. 1/3
Step-by-step explanation:
Divide by GCF
find square root of 82369 by division method step by step
Answer:
I think this ans may help you
What Is The Estimated Weight Of Three Containers Weighing 1.656 kg each? (Math 5 Quarter 2, Week 5) I Need A Nice And Clear Answer
Answer:
[tex]Estimate = 5.0kg[/tex]
Step-by-step explanation:
Given
[tex]Weight = 1.656kg[/tex]
Required
Determine the estimated for 3 containers
Since the weight of all containers are the same, we simply multiply the given weight by the number of containers.
i.e.
[tex]Estimate = Number\ of\ containers * Weight\ of\ each[/tex]
[tex]Estimate = 3 * 1.656kg[/tex]
[tex]Estimate = 4.968kg[/tex]
[tex]Estimate = 5.0kg[/tex] --- approximated
So, the estimated weight is 5.0kg
Cindy has a 4-shelf bookcase in which she wants to place baskets. Each basket takes up 1/4 of the shelf. How many baskets can Cindy place on the 4 shelves?
Answer:
16
Step-by-step explanation:
One basket takes (1/4)th of the shelf.
So, in one shell, Cindy can place 4 baskets
Total number of baskets = 4 *4 = 16
A city planner is studying the need for affordable housing in the city's Urban Planning Department. He learned from the census of all 75,342 households in the city that the median family income is $65,000, with an average of 2.9 persons-per-household, and 88% live in a single household unit. Previously, the planner had surveyed a group of 400 randomly selected households in the city. The surveyed households had a median family income of $52,000, an average of 3.2 persons per household, and 80% lived in a single household unit. 2
(a) For city planner's survey, identify the population and the sample,
Population: (Choose one)
Sample: (Choose one)
(b) Choose whether each number described below is a parameter or a statistic for the city planner's survey,
Number Parameter Statistic
The 80% of the group of randomly selected households that live in a single household unit
The average of 2.9 personer household of all the households in the city The $65,000 median family income of all the households in the city At a TV assembling facility, the Quality Assurance (QA) department tested a random selection of 600 TV's assembled in March.
Answer:
Population = 75,342 households
Sample = 400 randomly selected households
The percentage who live in a single household unit = Parameter
The average of 2.9 person per household of all households in the city = parameter
The $65,000 median family income of all the households in the city = Parameter
Step-by-step explanation:
The population refers to all the entire elements, observations or subject which fits into a particular study. In the scenario above, the entire household in the city of study. That is, the 75,342 households.
The sample is the subset of the population which is a smaller set of observation meant to be representative of the larger population. The sample here is the 400 randomly selected households.
Parameter differs from statistics in that numerical estimates or calculations obtained from the population is called the parameter while the numerical characteristics derived from the sample is called statistic.
In this exercise we have to use the knowledge of probability to calculate the chances of choosing a TV approved by the quality control, so:
400 randomly selected households
So, based on the information given in the statement, we have:
Population = 75,342 householdsSample = 400 randomly selected householdsSome parameters for this equation are:
The percentage who live in a single household unit The average of 2.9 person per household of all households in the cityThe $65,000 median family income of all the households in the cityThe inhabitants of a place refers to all the complete essential feature, attention or subject that fits into the study. In the sequence of events above, the complete household fashionable the city of study. That is, the 75,342 households.
The sample exist the subset of the inhabitants of a place that exist a tinier set of comment on something scrutinized intend expected representative of the best inhabitants of a place. The sample in this place happen the 400 carelessly picked households.
See more about statistics at brainly.com/question/10951564
The first correct answer gets brainliest
Answer:
1.2 Cm.
Step-by-step explanation:
If you multiply these three fractions you get 1.2 Cm. Or in fraction from 6/5
Hope this helped. Please correct me if I am wrong
Aramaic sequence how do you find the term
ILL GIVE 50 POINTS AND BRAINLIEST!!!
A business assistant must leave more than $50 in the supply account. There is $175 in the account. The assistant needs to order x boxes of pens that cost $6.50 each.
What is the maximum number of boxes of pens the business assistant can buy? Please show your math work and justify your answer.
which of these show equivalent fractions? A. 1/4=4/8 B. 1/2=2/4 C. 3/5 = 5/10 D. 2/3 = 3/6
What is the answer of 1/3 x 1/4
Answer:
1/12
Step-by-step explanation:
Multiply across
Hope this helps
WILL MARK BRAINLIEST ONLY HAVE 10 MINUTES AND DOUBLE POINTS:
Jack scored 7,9,2,6,15,15 points 6 basketball games. Find the mean,median and mode scores for all the games
Answer:
mean = 9
mode = 15
median = 8
Step-by-step explanation:
Each day after school, Chelsey runs 2.8 miles farther than Kyle.
Part A. Write an equation that represents the number of miles Chelsey runs, c, compared with Kyle, k.
plzz help
Part B. If Kyle runs 4 miles, how many miles does Chelsey run?
Answer:
6.8 miles
Step-by-step explanation:
First, create the equation representing Chelsey's miles compared to Kyle's:
c = k + 2.8
Next, find how many miles Chelsey runs if Kyle runs 4 miles.
Plug in 4 as k into the equation:
c = k + 2.8
c = 4 + 2.8
c = 6.8
So, Chelsey runs 6.8 miles
Answer:
Question :-Each day after school, Chelsey runs 2.8 miles farther than Kyle.
Part A. Write an equation that represents the number of miles Chelsey runs, c, compared with Kyle, k.
plzz help
Part B. If Kyle runs 4 miles, how many miles does Chelsey run?
Solution :-Let the miles walk by Chelesy be x
Now,
x = 4 + 2.8
x = 6.8 miles
Therefore,
x = Kyle's mile walked + 2.86.8 miles[tex] \\ [/tex]
25/35 and 10/14 simplified
Answer:
(25/5)/(35/5)
=> 5/7
(10/2)/(14/2)
=> 5/7
Hence both of the numbers simplify to 5/7
Hope it helps
You are charged $9.2 in total for a meal. Assuming that the local sales tax is 7.7%, what was the menu price of this item?
Answer:
9.91
Step-by-step explanation:
The length of a rectangle is twice the width. The area is 32 yd2. Find the length and the width.
W=4 ANS. FOR THE WIDTH. L=2*4=8 ANS.
Mark as brainlist
what is the LCM of 3and 6
Answer:
L.c.m of 3 and 6 is 6
Answer:
Lcm of 3&6 is:
3*2 & 6*1 (DONE LIKE THIS BECAUSE THAT LCM OF 3 & 6 IS FOUND TO BE 6 AS BOTH 3 & 6 HAS THE SMALLEST COMMON MULTIPLE AS 6)
6 & 6
There fore LCM is 6
Of all ladies over the age of 50, 72% report that they color their hair to hide their gray. What is the probability
that under 70% color their hair in a group of 85 older women?
Answer:
0.3409 = 34.09% probability that under 70% color their hair in a group of 85 older women.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the Central Limit Theorem.
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].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex].
72% report that they color their hair to hide their gray.
This means that [tex]\mu = p = 0.72[/tex]
What is the probability that under 70% color their hair in a group of 85 older women?
For a sample of 85, we have that [tex]s = \sqrt{\frac{0.72*0.28}{85}} = 0.0487[/tex]
This probability is the pvalue of Z when X = 0.7. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.7 - 0.72}{0.0487}[/tex]
[tex]Z = -0.41[/tex]
[tex]Z = -0.41[/tex] has a pvalue of 0.3409
0.3409 = 34.09% probability that under 70% color their hair in a group of 85 older women.
4(x + 3) + 2x = 6(x + 2)
Answer:
answer is 0
Step-by-step explanation:
The ordered pairs show amounts y (in inches) of rainfall equivalent to x inches of snow.(16, 1.5), (12, 1.3), (18, 1.8), (15, 1.5), (20, 2.1),(23, 2.4) About how many inches of rainfall are equivalent to 6 inches of snow? Round your answer to the nearest hundredth, if necessary.
Answer:
0.57 inches of rainfall is equivalent to 6 inches of snow
Step-by-step explanation:
The given data are presented here as follows;
[tex]\begin{array}{cc}x&y\\16&1.5\\12&1.3\\18&1.8\\15&1.5\\20&2.1\\23&2.4\\\end{array}[/tex]
The data points are approximately linear
From the the trend line of the plotted points of the graph, created with Microsoft Excel, with Forecasting, when there is 6 inches of snow the rainfall is 0.575 inches
By linear regression, we have;
Y = a + b·X
Where;
[tex]b = \dfrac{n \cdot \sum XY - \left (\sum X \right ) \cdot \left (\sum Y \right )}{n \cdot \sum X^{2} - \left (\sum X \right )^{2}}[/tex]
[tex]a = \dfrac{\sum Y - b \cdot \sum X}{n}[/tex]
∑x = 104
∑y = 10.6
∑(x·y) = 191.7
(∑x)·(∑y) = 1102.4
(∑x)² = 10816
n = 6
SigX^2 = 1878
Plugging in the values, gives;
[tex]b = \dfrac{6 \times191.7 - 1102.4}{6 \times 1878 - 10816} \approx 0.10575[/tex]
[tex]a = \dfrac{10.6 - 0.10575 \times 104}{6} \approx -0.06637[/tex]
Therefore;
Y = 0.10575·x - 0.06637
When x = 6 inches, we have;
Y = 0.10575 × 6 - 0.06637 = 0.56813
Y = 0.56813 inches ≈ 0.57 inches of rainfall
Therefore;
0.57 inches of rainfall is equivalent to 6 inches of snow
Find the slope between the two ordered
pairs: (3,-4) and (6,-5)
Answer:
-1/3
Step-by-step explanation:
-4 - -5 = 1
3 - 6 = -3
1/-3 = -1/3
Answer: -1/3
Step-by-step explanation: slope is the difference in the y values over the difference of the x values
Sarah had 8 guests at her birthday party. She cut her round cake into 12 equal slices. 8 of the slices were eaten. What is the angle measure of the cake that was left?
Answer:120°
Step-by-step explanation:
Given
cake is cut into 12 equal pieces
We know the top view of cake is similar to circle .
So, if a circle is divided into 12 equal parts then
each part subtend an angle of
∅ = 360/12 = 30%
If 8 slices were eaten , then 4 slices are remaining
These 4 slices measure subtend equal angle at the center therefore
4 slice measure a total of 4 × ∅
➡️ 4 x 30°
➡️ 120°
can I have the answer and a quick explanation plz?
Given:
A figure of a right triangle.
To find:
The value of x.
Solution:
According to the geometric mean attitude theorem, if an altitude is drawn from the right angle vertex to the hypotenuse, then the altitude is the geometric mean of segments of hypotenuse.
Using geometric mean attitude theorem, we get
[tex]\dfrac{3}{x}=\dfrac{x}{5}[/tex]
[tex]3\times 5=x\times x[/tex]
[tex]15=x^2[/tex]
[tex]\pm \sqrt{15}=x[/tex]
But side cannot be negative. So,
[tex]\sqrt{15}=x[/tex]
Therefore, the value of x is [tex]\sqrt{15}[/tex].
In the rectangle below what is X
Answer:
X = 114
Step-by-step explanation:
if one corner is 33 degrees. and the opposite corner is the same then you know that makes 66 degrees.
you take that minus 180. so 66 - 180 which leaves 114.
so X is 114
A fair 10 sided dice numbered 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 is rolled once. What is the PERCENTAGE probability that it lands on a number that is prime? *
Answer:
40% probability that it lands on a number that is prime.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
10 sided dice
So 10 total outcomes.
Prime numbers:
Of those, 2, 3, 5 and 7 are prime, so 4 of the outcomes.
4*100/10 = 40%
40% probability that it lands on a number that is prime.
A car manufacturer announced that next year the price of a certain model car would increase by 3.5%. This year the price is $15,649 . The increase in the price of the car is $? The new price of the car is $?
The increase will be the original price x the increase rate.
15649 x 0.035 = $547.72
The new price would be original price + increase
15649 + 547.72 = $16,196.72
Six out of the 12 members of the school choir boys. In the simplest form, what fraction of the choir is boys? Pls help out with this question