The mean speed of a sample of vehicles along a stretch of highway is 69
miles per hour, with a standard deviation of 4 miles per hour. estimate the percent of vehicles whose speeds are between 65 miles per hour and 73 miles per hour. (assume the data set has a bell-shaped distribution.)
approximately what % of vehicles travel between 65 miles per hour and 73
miles per hour.

cheater

step-by-step explanation:

27 +27 or 27times 2=54

the diffrence is 0

yes, gavin is right.

step-by-step explanation:

gavin is correct. 

this problem is about converting 9% per year to how many percent per quarter. the rate is still the same. it only differed in the time period. so, through dimensional analysis,

9% per year  × (1 year / 4 quarters) = 2.25% per quarter

if he was asked to convert 9% per year to how many percent per quarter  compounded quarterly, then you will not simply divide by four. this is because compounding is not linear.

hope this , have a good day. c;