there is a sandbox with a width of 6ft and a length of 10ft, suppose the length and the width are doubled.
a. find the percent of change in the perimeter
b. find the percent of change in the area
i think the answer is 66.67% for both of them
don't understand how you came up with that answer.
old sandbox : 6 by 10
so perimeter = 32 ft
area = 60 ft^2
new sandbox : 12 by 20
new perimeter = 64 --> it doubled, so a 100% increase, the multiplication factor is 2
new area = 240 ft^2 --> it quadrupled
so the increase is 300% , the multiplication factor was 4
in general, since perimeter is a linear measurement, the perimeter would be the same multiplication factor
and the area would be the (multiplication factor)^2
e.g. If we had tripled the dimensions, the area would be 9 times as large