The scores on an exam are normally distributed, with a mean of 74 and a standard deviation of 7. what percent of the scores are less than 81? the scores on an exam are normally distributed, with a mean of 74 and a standard deviation of 7. what percent of the scores are less than 81?

We are given the following variables:

Normal distribution

u = sample mean = 74

s = standard deviation of the samples = 7

x = sample value = 81

Since we are asked to find percent of the scores less than 81, this means we have to find the proportion using the z-score. The formula for z score is:

z = (x – u) / s

Substituting the given values:

z = (81 – 74) / 7

z = 1

Using the standard normal distribution tables for z, we find that:

P = 0.8413            at z = 1

Therefore this means that 84.13% of scores are less than 81.

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm

the length of o'p' is .

step-by-step explanation:

it is given that the quadrilateral m'n'o'p' is the image of quadrilateral mnop after dilation.

the center of dilation is origin and the scale factor is 1.5.

in dilation the image and preimge are similar figures. it means the sides of image and preimage are proportional.

the scale factor is defined as

the scale factor is 1.5.

multiply both sides by op.

note: if the value of op is given, then multiply the value of op with 1.5 to get the length of side o'p'.

therefore length of o'p' is .