SOLUTION: A cyclist rode the first 20 mile portion of his workout at a constant speed. For the 16 mile cooldown portion of his owrkout, he reduced his speed by 2 miles per hour. Each porti

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Question 507577: A cyclist rode the first 20 mile portion of his workout at a constant speed. For the 16 mile cooldown portion of his owrkout, he reduced his speed by 2 miles per hour. Each portion of the workout took the same time. Find the cyclist's speed during the first portio and find his peed during the cooldown portion.
Answer by ankor@dixie-net.com(22740) (Show Source):
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A cyclist rode the first 20 mile portion of his workout at a constant speed.
For the 16 mile cooldown portion of his workout, he reduced his speed by 2 miles per hour.
Each portion of the workout took the same time.
Find the cyclist's speed during the first portion and find his speed during the cool down portion.
:
Let s = his speed for the 1st 20 mi
then
(s-2) = his speed for the last 16 mi
:
Write a time equation; time = dist/speed
:
initial time = cool-down time
=
cross multiply
20(s-2) = 16s
20s - 40 = 16s
20s - 16s = 40
4s = 40
s =
s = 10 mph, his initial speed
then
10 - 2 = 8 mph his cool-down speed
;
:
Check this by finding the actual times
20/10 = 2 hrs
16/8 = 2 hrs also