A group of 500 elders completed a test of cognitive functioning. the mean score was 85, the standard deviation was 5, and scores were normally distributed. approximately what percentage of the 500 scores fell between 80 and 90?

By the Empricial Rule, approximately 68% of the 500 scores fell between 80 and 90

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviation of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean = 85

Standard deviation = 5

Approximately what percentage of the 500 scores fell between 80 and 90?

80 = 85 - 5

So 80 is one standard deviation below the mean

90 = 85 + 5

So 90 is one standard deviation above the mean

By the Empricial Rule, approximately 68% of the 500 scores fell between 80 and 90

the figures below are made out of circles, semicircles, quarter … find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations). remember that we'll also have to cut whatever areas we get in half, since we're only dealing

step-by-step explanation:

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk