LESSON 8 SESSION 4<br> What is the slope of this line

An English professor assigns letter grades on a test according to the following scheme. A: Top 14% of scores B: Scores below the

NeX [460]

Answer:

Grades between 62 and 64 result in a D grade.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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.

In this problem, we have that:

$\mu = 71.9, \sigma = 7.8$

Find the numerical limits for a D grade.

D: Scores below the top 84% and above the bottom 10%

So below the 100-84 = 16th percentile and above the 10th percentile.

16th percentile:

This is the value of X when Z has a pvalue of 0.16. So X when Z = -0.995.

$Z = \frac{X - \mu}{\sigma}$

$-0.995 = \frac{X - 71.9}{7.8}$

$X - 71.9 = -0.995*7.8$

$X = 64$

10th percentile:

This is the value of X when Z has a pvalue of 0.1. So X when Z = -1.28.

$Z = \frac{X - \mu}{\sigma}$

$-1.28 = \frac{X - 71.9}{7.8}$

$X - 71.9 = -1.28*7.8$

$X = 62$

Grades between 62 and 64 result in a D grade.

6 0

3 years ago

Simon used 3 pears and 9 apples to make a fruit salad. What is the ratio of the number of pears to the number of apples in the f

Yanka [14]

Answer:

1 : 3

Step-by-step explanation:

pears : apples = 3 : 9 = 1 : 3

___

A common factor of 3 can be removed from each number in the ratio to reduce it to lowest terms.

3 0

3 years ago

Find the set the solves <br> <img src="https://tex.z-dn.net/?f=x%20%2B%20%20%20%5Cfrac%7B2%7D%7Bx%7D%20%20%20%5Cgeq%203" id="Tex

Nady [450]

Hello,
To exist x≠0

if x>0 then
x+2/x>=3==>x²+2>=3x
==>x²-3x+2>=0
==>(x-2)(x-1)>=0 positive out of the roots
==> (x<=1 or x>=2) and x>0
==>(0<x<=1) or (x>=2)
else
x<0
x+2/x>=3==>x²+2<=3x
==>x²-3x+2<=0 negative betheen the roots
==>(1<=x<=2) and x<0 : no solution
end if

4 0

3 years ago

An electronics store received two shipments of radios. Of the 250 radios in the first shipment, exactly 6% were damaged. In the

nataly862011 [7]

Answer:

Total number of not damaged = 451

C. 451

Step-by-step explanation:

In the first shipment, 6% of the 250 radios where damaged.

Number of damaged= 6/100 * 250

Number of damaged= 6*2.5

Number of damaged= 15 radios.

Number of not damaged= 250-15

Number of not damaged = 235 radios

In the second shipment, 4% of the radios were damaged

Let the number of second shipment= y

0.04 of y where damaged

Total number of radio damaged= 24

15 + 0.04y = 24

0.04y= 24-15

0.04y = 9

Y= 9/0.04

Y= 225

Number of radio in the second shipment= 225

Number of damaged in the second shipment= 0.04*225

Number of damaged in the second shipment= 9

Number of not damaged in the second shipment= 225-9

Number of damaged in the second shipment= 216

Total number of not damaged

= 235+216

= 451

Total number of not damaged= 451

7 0

3 years ago

Find the value of the variable.

Alinara [238K]

Answer:

x = 25√2, y = 25

Step-by-step explanation:

x = 25(√2) = 25√2

y = 25

8 0

2 years ago

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LESSON 8 SESSION 4 What is the slope of this line