there are two concentric circles on the playground. The diameter of the larger circle is 40% greater than the diameter of the smaller circle. The area of the larger circle is what percent greater than the area of the smaller circle
Let D1-------------------- >diameter of the larger circle D2-------------------- >diameter of the smaller circle D1=D2*1.4----------- > D2=D1/1.4
A1--------------- > Area of the larger circle A2--------------- > Area of the smaller circle A1=pi*D1²/4 A2=pi*D2²/4----------- > pi*D1²/(1.4² *4)-------- >A1/1.4²------ > A1*(0.51) A2=0.51A1---------- > A1=A2/0.51=1.96 A2 A1=1.96A2
The answer is the area of the larger circle is 96% greater than the area of the smaller circle