# Math

It took Jen, who biked at a speed of 12 mph, 20 minutes to get home. What is Jim’s speed, if it took him only 15 minutes to bike that distance?

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1. distance = speed * time

Since their distances are the same, if Jim's speed is x, then

x(1/4) = (12)(1/3)
x = 16 mi/hr

Or, you can consider it like this. Jim takes 3/4 as long, so his speed must be 4/3 as great.

4/3 * 12 = 16

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2. How did you get 1/4 and 1/3 and4/3

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4. Yeah, its right

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5. yes!

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6. very nice!

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