Question

How many square inches greater is the area of a 30-inch circular mirror than an 18-inch circular mirror?

Answer 1

Area of a 30-inch circular mirror is greater than area of a 18-inch circular mirror by 452.16 square inches.

Explanation:

We are given the following in the question:

Mirror 1:

`d_1 = 30\text{ inches}\\\\\Rightaroow r_1 = (30)/(2)=15\text{ inches}`

Area of mirror 1 = Area of circle

`A_1 = \pi r_1^2`

Putting values, we get,

`A_1 = 3.14* (15)^2=706.5\text{ square inches}`

Mirror 2:

`d_1 = 18\text{ inches}\\\\\Rightaroow r = (18)/(2)=9\text{ inches}`

Area of mirror 1 = Area of circle

`A_2 = \pi r_2^2`

Putting values, we get,

`A_2 = 3.14* (9)^2=254.34\text{ square inches}`

Difference between area =

`=A_1-A_2\\=706.5-254.34\\=452.16\text{ square inches}`

Thus, area of a 30-inch circular mirror is greater than area of a 18-inch circular mirror by 452.16 square inches.