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The circumferences of two circles are in the ratio of 2:5. The radius of the smaller circle is 16 in. What is the radius of the larger circle?

32 in.
40 in.
80 in.
160 in.

User Arif Eqbal
by
7.6k points

1 Answer

2 votes

Answer:

The radius of the larger circle is 40 inches.

Get first the circumference of the smaller circle.

C = 2πr; Where π = pi; r = radius

= 2(3.14)(16)

C = 100.48

Now get the circumference of the bigger circle using ratio:

2/5 = 100.48/C

2C = 502.4

2C/2 = 502.4/2

C = 251.2

Using the circumference, compute for the radius of the larger circle:

r = C/2π; Where C = circumference; π = pi

= 251.2/2(3.14)

= 251.2/6.28

r = 40

To check:

C = 2(3.14)(40)

251.2 = (6.28)(40)

251.2 = 251.2

Explanation:

User Maalamaal
by
8.2k points