A. CHild jumping rope can jump at a speed of 280 revolutions every two minutes what is the number of revolutions the child can jump in 3.5 minutes

the number of revolutions the child can jump in 3.5 minutes is 490 .

Step-by-step 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 .

c. 4 1/4 pounds

38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this