the number of revolutions the child can jump in 3.5 minutes is 490 .
Explanation:
Here we have , A child jumping rope can jump at a speed of 280 revolutions every two minutes . We need to find what is the number of revolutions the child can jump in 3.5 minutes . Let's find out:
According to question , A child jumping rope can jump at a speed of 280 revolutions every two minutes , So in one minute Number of revolutions is :
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Now , the number of revolutions the child can jump in 3.5 minutes :
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Therefore , the number of revolutions the child can jump in 3.5 minutes is 490 .