SOLUTION: A cyclist and a jogger start from a town at the same time and head for a destination 12 mi away. The rate of the cyclist is twice the rate of the jogger. The cyclist arrives 1.2 h

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Question 1055125: A cyclist and a jogger start from a town at the same time and head for a destination 12 mi away. The rate of the cyclist is twice the rate of the jogger. The cyclist arrives 1.2 h before the jogger. Find the rate of the cyclist.
Answer by ikleyn(52784) About Me  (Show Source):
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A cyclist and a jogger start from a town at the same time and head for a destination 12 mi away.
The rate of the cyclist is twice the rate of the jogger. The cyclist arrives 1.2 h before the jogger. Find the rate of the cyclist.
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One equation is

12%2Fj+-+12%2Fc = 1.2,   (1)

where j is the jogger's rate, c is the cyclist's rate.

The other equation is 

c = 2j.                    (2)

Substitute (2) into (1). You will get

12%2Fj+-+12%2F%282j%29 = 1.2.

Multiply both sides by (2j). You will get

24 - 12 = 2.4j  --->  12 = 2.4j  --->  j = 5 mph.

Then c = 10 mph.

Solved.