Question

The radius of the bull’s-eye of the dartboard is 8 inches. The radius of each concentric circle is 8 inches more than the radius of the circle inside it. If a dart lands at random on the dartboard, what is the probability that the dart will hit in area C?

Answer 1

A. 9/16
B. 5/16
C. 1/4
D. 3/4

Answer 2

@ganeshie8

Answer 3

@ranga

Answer 4

Divide the area of the region marked C by the total area of the dartboard.

Region Radius
A 8
B 16
C 24
D 32

Total area of dartboard = pi * (32)^2
Area of region marked C = pi * (24^2 - 16^2)

Answer 5

Total area: 3215.36
Area of C: 1004.8

Answer 6

Yes, 1004.8 / 3215.36 = 0.3125. But put it in fraction.

Answer 7

5/16

Answer 8

Yes.

Answer 9

thanks :)

Answer 10

There is a way to do this without using a calculator.

Area of region marked C = pi * (24^2 - 16^2) = pi * (24+16) * (24-16) = pi*40*8
Total area of dartboard = pi * 32^2
ratio = (pi*40*8) / (pi*32*32) = 320/(32*32) = 10/32 = 5 /16

Answer 11

ok thanks

Answer 12

you are welcome.