In a health club, research shows that on average, patrons spend an average of 42.5 minutes on the treadmill, with a standard deviation of 5.4 minutes. it is assumed that this is a normally distributed variable.

find the probability that randomly selected individual would spent between 30 and 40 minutes on the treadmill.

a)0.38

b)0.69

c)0.99

d)0.31

d) 0.31

Step-by-step explanation:

Given : In a health club, research shows that on average, patrons spend an average of 42.5 minutes on the treadmill, with a standard deviation of 5.4 minutes.

i.e. and

It is assumed that this is a normally distributed variable.

Let x denotes the time spend by a person on treadmill.

Then, the probability that randomly selected individual would spent between 30 and 40 minutes on the treadmill.

Hence, the required probability = 0.31

Thus , the correct answer = d) 0.31

c. y = 1/4 x + 5

step-by-step explanation:

first, put the equation of the line on the graph into slope-intercept form

(y = mx + b):   y = -4x + 8

second, a perpendicular line has to have "an opposite/reciprocal slope" to the original slope. so, find the "m" value in your original equation (it's -4, right? )

original slope: m = -4   perpendicular slope: change the sign to its opposite and find the reciprocal ("flip" the number)

new slope is now positive (b/c the original slope was negative 4), and it's 1/4 (not the original slope of 4 or 4/1)