A cyclist travels

A cyclist travels the length of a bike path that is 225 miles long, rounded to the nearest mile. If the trip took him 5 hrs, rounded to the nearest hour, then his average speed must be between:

A. 38 and 50 mph
B. 40 and 50 mph
C. 40 and 51 mph
D. 41 and 50 mph
E. 41 and 51 mph

My Ques: How do we do the approximation and define the range?

Expert Asked on March 29, 2018 in

Hi Riya,

If the distance is 225 miles rounded to the nearest mile, the range for the distance is 224.5 < = Distance < = 225.5.

Similarly since the time is 5 hours rounded to the nearest hour, the range for the time is 4.5 < = Time < = 5.5.

So to get the range we just need to find the extreme values.

224.5/5.5 will be the lowest possible speed since we are considering the lowest numerator and the highest denominator. = 40.8

225.5/4.5 will be the greatest possible speed since we are considering the highest numerator and the lowest denominator = 50.1

So the range here has to be between 40 and 51.

Expert Answered on April 20, 2018.