2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.

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:

$\mu = 36, \sigma = 5$

The first step to solve this question is finding the proportion of students which use the computer more than 40 minutes, which is 1 subtracted by the pvalue of Z when X = 40. So

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

$Z = \frac{40 - 36}{5}$

$Z = 0.8$

$Z = 0.8$ has a pvalue of 0.7881.

1 - 0.7881 = 0.2119

So 21.19% of the students use the computer for longer than 40 minutes.

Out of 10000

0.2119*10000 = 2119

2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.

8 0

3 years ago

At an university 70% of the students who attend stay on campus. If 1,380 of the students who attend live off campus, what is the

Alborosie

Answer:

4600

Step-by-step explanation:

We can write a proportion to find the total amount who attend university using the information given. A proportion is two equivalent ratios set equal to each other. Since 70% live on campus, then 30% live off campus and we are told that number is 1,380.

$\frac{30}{100}=\frac{1380}{y}$

We will cross multiply the numerator of one ratio with denominator of the other. And then solve for y.

30y=100(1380)

30y=138000

y=4600.

There are 4600 students who attend the university.

7 0

3 years ago

At the market you can buy 5 bags of apples for $23.60. At the orchard you can get 7 bags of apples for 32.76. Which is the bette

mars1129 [50]

So you want to find the price for 1 apple you find that by dividing so 23.60/5=4.72
and 32.76/7=<span>4.68
so, the 7 bag for 32.76 is the better deal</span>

5 0

3 years ago

Read 2 more answers

Can someone help!!! And explain please

vlada-n [284]

Answer:

400(π+2) feet square

Step-by-step explanation:

let x be the diagonal of the cage=40√2 at the same time it is the radius of the circle ( the tiger can go in circle)

but since the cage is part of the circle and not full turn πr²/8

area of the circleπr²+ half area square

(π(40√2)²)/8 +40²/2

3200π/8+1600/2

400π+800

400(π+2) feet square

6 0

3 years ago