Ming needs to play for 15 hours to get 500 points. They gave him 200 for signing up, so 500-200=300 more points needed. 300 divided by 20= 15 more hours.
Here you go, hope it helps:)
With a square, all you need to do to find the length of one side is to divide the perimeter by 4. If it is the area you are calculating, then you need to find the square root. For that equation the answer is 24.
