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 :

⇒

⇒

⇒

Now , the number of revolutions the child can jump in 3.5 minutes :

⇒

⇒

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

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions