Question

If you burn 450 calories per hour when rollerblading how many calories will you burn in 20 minutes

Answer 1

First find how many calories burned in minute by dividing 450 by 60.
450/60 = 7.5

Then multiply this by 20.

7.5*20 = 150

150 calories burned in 20 minutes.

Alternatively, 20 minutes is one third of an hour, so 450 may be multiplied by 1/3. This gives the same answer.

Answer 2

1 hour = 450 calories

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Rewrite 1 hour as 60 mins :
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60 mins = 450 calories

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Divide by 3 through :
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20 mins = 450 ÷ 3
20 mins = 150 calories

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Answer: 20 mins burns 150 calories.
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