Suppose a normally distributed set of data has a mean of 178 and a standard deviation of 20. Use the 68-95-99.7 Rule to determine the percent of scores in the data set expected to be below a score of 218. Give your answer as a percent and include as many decimal places as the 68-95-99.7 rule dictates. (For example, enter 99.7 instead of 0.997.)

97.7%

Step-by-step explanation:

For a score below 218 :

P(x < 218)

Standard deviation = 20 ; mean = 178

Obtian the standardized score (Zscore) :

Zscore = (x - mean) / standard deviation

Z = (218 - 178) / 20 = 40 / 20 = 2

P(x < Z) = P(Z < 2) = 0.97725 (Z probability calculator)

0.97725 * 100 = 97.725 = 97.7%

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