Question

Work out the circumference and area of the circular piee of glass needed for the top of a display cabinet which has a diameter of 1.8m. Use #=3.14? Circumference = in m and Area = in m2

Answer 1

Hello there!

Answer:

Circumference:
`l = 2\pi r = 2*3.14*0.9 = 5.652 (m)`

Area:
`S = \pi r^2 = 3.14 * 0.9^2 = 2.5434(m^2)`

Explanation:

We should know 2 important formulas:

Circumference:
`l = 2\pi r`

Area:
`S = \pi r^(2)`

So we need to find the value of r (radius) which equal to a half of diameter:

`r = d/2`

`r = 1.8/2 = 0.9(m)`

Circumference:
`l = 2\pi r = 2*3.14*0.9 = 5.652 (m)`

Area:
`S = \pi r^2 = 3.14 * 0.9^2 = 2.5434(m^2)`