Answer:
a) 68%
b) 99.7%
c) 95%
Step-by-step explanation:
The mean height for an 8th grader in the State of Florida is 146 cm with a standard deviation of 8 cm. Given a normal distribution, use the Empirical Rule to interpret the data.
Empirical rule states that:
68% of data falls within 2 standard deviations from the mean - between μ – σ and μ + σ .
95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
Mean = 146
Standard deviation = 8cm
a) What percent of 8th graders heights are between 138 cm and 162 cm?
146 - sx = 138cm
146 - 138 cm = 8cm
146 - 162 cm = 8cm
Hence,68% of data falls within 2 standard deviations from the mean - between μ – σ and μ + σ .
b) What percent of 8th graders heights are between 122 cm and 170 cm?
Standard deviation = 8
146 - 122 = 24 cm
146 - 170 = -24cm
24cm/8 cm = 3
Hence,99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
c) What percent of 8th graders heights are between 130 cm and 162 cm?
146 cm - 130cm = 16cm
162 cm - 146 cm = 16 cm
16cm/8cm
= 2
Hence, 95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
If three cards are drawn at random from a standard deck of 52 cards, what is the probability that they will all be queens?
Answer:
0.01809955% or about 0.018%
Step-by-step explanation:
You do the multiplication of 4/52 by 3/51 by 2/50
Find the value of x
Answer: x= 108
Step-by-step explanation: The triangle is an isosceles triangle, so the two sides are parallel which means the other angle equals to 72 as well. Now we take the triangle rule and do 180-72-72= 36 (the top angle= 36). The triangles are all equal so that means the other angle (in the upside down one) also equals 72 so we take 36+72= 108. Since it is also a parallelogram, the angles are equal.
please help me :(
Angharad sleeps for 8 hours each night, correct to the nearest 10 minutes.
The total time she sleeps in the month of November (30 nights) is T hours.
Between what limits does T lie?
Answer:
The limits between which T lies is 273 hours 30 mins < T < 242 hours 30 minutes
Step-by-step explanation:
The number of hours Angharad sleeps each night = 8 hours ± 10 minutes
The actual time Angharad sleeps each night = 8 hours ± 5 minutes
Which gives the maximum time Angharad sleeps = 8 hours 5 minutes = 485 minutes per night
The minimum time Angharad sleeps = 7 hours 55 minutes = 475 minutes
The number of days in the month of November = 30 nights
The maximum time in minutes Angharad sleeps in November, [tex]T_{max}[/tex] = 30 nights × 485 minutes/night = 14,550 minutes = 242.5 hours = 242 hours 30 minutes
The minimum time in minutes Angharad sleeps in November, [tex]T_{min}[/tex] = 30 nights × 475 minutes/night = 14,250 minutes = 237.5 hours = 237 hours 30 minutes
Therefore, we have, the limits between which T lies given as follows;
273.5 hours < T < 242.5 hours.
Answer:
235 ≤ T ≤ 245
Step-by-step explanation:
(8 hours per night x 30 nights) = 240 hours
The deviation from 8 hours per night is as much as 10 minutes per night.
Over 30 nights, the total deviation can be as much as (30 x 10 minutes) = 300 minutes = 5 hours.
So T can be as much as (240 + 5) = 245 hours, or as little as (240 - 5) = 235 hours.
In inequality form,
235 ≤ T ≤ 245
5) Phillip earns $11.25 per hour. During Week 1, he worked h hours. During Week 2, he worked 8
hours more than Week 1. If Phillip earned $540 for both weeks, how many hours did he work
during Week 2?
Answer:
2,160 Hours
Step-by-step explanation:
Ok so usual i would split $540 in half so a number multiplied by two would end up as 540, and i got 270. So since each week we know Phillip earned $270 and $11.25 a hour, we can divide 270 by 11.25, which gives us $24, so that means h = 24, but on week 2 it says Phillip worked 8 hours more on week 2, so that gives us a equation of 8 x 11.25, which comes out to 90, so now we can move on to our final equation, 90 x 24, which equals 2160. Im so sorry if this is wrong
Phillip worked for 20 hours and 28 hours in 1 and 2 weeks respectively.
What is unit rate?A unit rate means a rate for one of something. We write this as a ratio with a denominator of one. For example, if you ran 70 yards in 10 seconds, you ran on average 7 yards in 1 second. Both of the ratios, 70 yards in 10 seconds and 7 yards in 1 second, are rates, but the 7 yards in 1 second is a unit rate.
Given that, Phillip earns $11.25 per hour. During Week 1, he worked h hours. During Week 2, he worked 8 hours more than Week 1. Phillip earned $540 for both weeks,
The unit rate for the work of Phillip is given, $11.25 per hour.
Therefore, his earning for h hours = $11.25h
For (8+h) hours = $11.25(h+8)
Since, he earned $540 for both weeks,
Therefore,
11.25(h+8) + 11.25h = 540
11.25h + 90 + 11.25h = 540
22.5h = 450
h = 20
h+8 = 28
Hence, Phillip worked for 20 hours and 28 hours in 1 and 2 weeks respectively.
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what is 25% more than 6 feet
Answer:
7.5 I guess?
Step-by-step explanation:
??
Step-by-step explanation:
l dont understand this can you explain
If f(x) = 1/2x^2 - (1/4x +3), what is the value of
f(8)?
Answer:
27
Step-by-step explanation:
If [tex]f(x) = \frac{1}{2x^2} - \frac{1}{4x +3}[/tex], then the value of [tex]f(8)[/tex] is [tex]f(8) = \frac{-93}{4480}[/tex].
What is Quadratic Equation?A quadratic equation is an algebraic equation in the variable of the second degree. The quadratic equation is in the form of [tex]ax^{2} + bx + c = 0[/tex], where [tex]a,b,c[/tex] are the real numbers.
We have
[tex]f(x) = \frac{1}{2x^2} - \frac{1}{4x +3}[/tex]
According to Quadratic Equation,
[tex]f(x)=ax^{2} +bx+c[/tex]
And we have,
[tex]f(x) = \frac{1}{2x^2} - \frac{1}{4x +3}[/tex]
So,
[tex]f(8) = \frac{1}{2x^2} - \frac{1}{4x +3}[/tex]
i.e. putting [tex]x=8[/tex],
[tex]f(8) = \frac{1}{2(8)^2} - \frac{1}{4*8 +3}[/tex]
[tex]f(8) = \frac{1}{128} - \frac{1}{35}[/tex]
Solving the above part,
[tex]f(8) = \frac{ 35-128 }{ 128*35 }[/tex]
[tex]f(8) = \frac{-93}{4480}[/tex]
Hence, we can say that value of [tex]f(8) = \frac{-93}{4480}[/tex] .
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algebra/algebra 2
The metric unit of force is the Newton (N) , which is kg⋅m/s2 .
Convert 10 kg⋅cm/s2 to Newtons.
1×10−1 N
1×10−2 N
1×10−5 N
1×10−6 N
Answer:
B
Step-by-step explanation:
If it’s right can you mark me brainliest ty
The conversion of 10 kg⋅cm/s2 in Newton is 1×10−1 N so option (A) will be correct.
What is unit conversion?To convert any unit into another is called a unit conversion.
In order to convert units, we need to care about their dimensions their dimension should not be changed.
For example conversion of a kilometer to a meter is to multiply by 1000 but meter and kilometer both unit is for distance only.
Another example could be kilo gram to gram.
Given the metric unit of force,
10 kg⋅cm/s²
Since,
1 meter = 100 cm ⇒ 1 centimeter = 0.01meter
So,
10 kg⋅cm/s² = 10 kg (0.01)m/s²
10 kg⋅cm/s² = 10 × 0.01 kg m/s²
10 kg⋅cm/s² = 1×10−1 kg m/s²
Since,
kg m/s² = Newton (N)
So,
10 kg⋅cm/s² = 1×10−1 N
Hence "The conversion of 10 kg⋅cm/s2 in Newton is 1×10−1 N ".
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Can someone please help!!
Answer:
Step-by-step explanation:
the last one
Write a recursive formula for the
sequence
12,27,42,57.....
HELP ME PLEASE I DO ANYTHING I BEEN STUCK FOR 30mins now
Answer: Adding 15 each time
which expression is equal to -3(4x - 2) - 2x?
Answer:
-14x + 6
Step-by-step explanation:
-12x + 6 - 2x
-14x + 6
ten subtracted from a number if the difference is 30 what was the orginal number
Please help me with this .
Answer:
x=4
Step-by-step explanation:
It's a parallel line so the equation is
100+19x+4=180
19x=180-100-4
19x=76
x=76/19
x=4
Answer: x = 4
Step-by-step explanation: The 2 angles are same-side interior angles, which are supplementary, and supplementary angles add up to 180, so we know that 19x + 4 = 80.
- 4. -4
19x = 76
/19. /19
X = 4
The manager of a clothing store purchased 40 pairs of jeans for $500. She plans to sell each pair of jeans for $19.99. By what percent did she mark up the price?
A.
60%
B.
12.5%
C.
10%
D.
7.5%
Answer:
60%
Step-by-step explanation:
Formula: Markup Percentage = Selling Price Per Unit - Cost Price Per Unit over Cost price per unit. times 100
$19.99 - 12.5
------------------- times 100
12.5
Follow PEMDAS
7.49 / 12.5 = 0.5592 (100) = 59.92
Round to the nearest whole number. So about 60%
Charles charges 4 an our to baby sit he also adds an extra 10 dollars onto the total for families with more than 3 children. How much will charles charge to baby sit 4 children for 4 hourss
Answer:
i beleve 26 or 48
good luck
On a Cartesian plane, the horizontal axis is called the _______ -axis and the vertical axis is called the _______-axis.
Answer:
Step-by-step explanation:
horizontal = x-axis
vertical = y-axis
Hope this helps!
Answer:
Horizontal: X-axis; Vertical: Y-axis
Step-by-step explanation:
At 8:00, the temperature was 15 degrees Celsius (°C). Three hours later, the temperature was -15°C. By how many degrees Celsius did the temperature change?
Answer:
30 degrees
Step-by-step explanation:
If you were to draw a number line, 15 and -15 are both 15 units away from 0. So, 15 + 15 =30
Please brainlist!
The coordinates of the turning point of the graph of
y = x
2 − 8x + 25 is (4,9).
Hence describe the single transformation which maps
the graph of y = x
2 onto the graph of
y = x
2 − 8x + 25.
Answer:
(x + 4), (y + 9)
Step-by-step explanation:
y= x^2 and y = x^2 - 8x + 25 are parabolas which open upwards.
The turning point of y = x^2 is at the origin (0, 0).
So the transformation is 4 units to the right and 9 units upwards:
(x + 4), y+ 9).
What is the slope of 7,-2 and -3,3
Answer:
-1/2
Step-by-step explanation:
y2-y1/x2-x1
3-(-2)/ -3-7
5/-10
= -1/2
I NEEP HELP ASAP PLEASE AND THANK YOU
Answer:
The first answer, 3 times the square root of x squared is correct.
Which is the value of the expression when x=-2 and y =-3
Answer:
-720
Step-by-step explanation:
10x^3y^2 If x = -2 and y = -3
10 * (-2^3) * (-3^2)
10 * (-8) * (9) = -720
Answer:
A.) -720
Step-by-step explanation:
10x^3y^2
10 times x^3 times y^2
x = -2
y = -3
10 times (-2)^3 times (-3)^2
-2^3 = -2 x -2 x -2 = -8
-3^2 = -3 x -3 = 9
-8 x 9 = -72
10 x -72 = -720
find the solution to following system using substitution or elimination
y = -x + 10
y = 7x + 2
A. (1,9)
B. ( 3/2 , 17/2)
C. (9,65)
D. (1, -1/7)
Answer:
the answer is (1,9)
Step-by-step explanation:
is this set of ordered pairs of a function?
(1,1) (2,3) (3,4) (4,2) (5,1)
What is the least amount of additional money Sofia can spend to get the sushi they need?
Answer:
$
Step-by-step explanation:
Circle D is shown. Line segment G D is a radius, D F is a radius, and D E is a radius. Angle G D F is 126 degrees, and angle F D E is 41 degrees. Point C is on the circle within angle G D F and point H is on the circle within angle G D E. Which statements are correct? Check all that apply.
Answer:
2,3,4 are correett
Step-by-step explanation:
1,5,6 are wroongg
Answer: 2 3 4 are your answers
what is the lowest term of 27/45
Answer:
3/5
Step-by-step explanation:
[tex] \frac{27}{45} = \frac{27 \div 9}{45 \div 9} = \frac{3}{5} \\ [/tex]
I need help!! ASAP!!
Answer:your answer is c
Step-by-step explanation:if you want to be friends we can just friend me
NEED HELP ASAP!!!!!!
Answer:
x=57
Step-by-step explanation:
63+60= 123
A triangle is 180 degrees
180-123= 57
x=57
Answer:
pretty sure x = 57
Step-by-step explanation:
60 + 63 = 123
180 - 123 = 57
Help please due in an 1 hour!!
Answer:
275
Step-by-step explanation:
1375-550/5-2
Answer:
275 per minute
Step-by-step explanation:
550/2=275
1375/5=275
2200/8=275
3025/11=275
therefore it is 275 ft. per minute
5. A train travels two different routes: the North Route and the South Route. • On Monday, the train traveled the North Route 8 times and the South Route 10 times, traveling a total of 410 miles. • On Tuesday, the train traveled the North Route 15 times and the South Route 11 times, traveling a total of 575 miles. How long is each route?
Answer:
North Route is 20 miles, and South Route is 25 miles.
Step-by-step explanation:
Let the length of the North route be represented by x and that of the South route be represented by y.
On Monday,
8x + 10y = 410
On Tuesday,
15x + 11y = 575
So that,
8x + 10y = 410 .............. 1
15x + 11y = 575 ......... 2
Using substitution method, from equation 1;
x = [tex]\frac{410 - 10y}{8}[/tex] ................. 3
Substitute the expression for x into equation 2,
15([tex]\frac{410 - 10y}{8}[/tex]) + 11y = 575
multiply through by 8,
6150 - 150y + 88y = 4600
6150 - 62y = 4600
6150 - 4600 = 62y
1550 = 62y
divide through by 62 to have,
y = 25
Substitute the value of y in equation 3
x = [tex]\frac{410 - 10y}{8}[/tex]
= [tex]\frac{410 - 10(25)}{8}[/tex]
= 20
x = 20
Thus, North Route is 20 miles, and South Route is 25 miles.
What is the value of x?
Enter your answer in the box
Answer:
The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try! A variable doesn't have to be "x", it could be "y", "w" or any letter, name or symbol.
Step-by-step explanation: