Question

findareaofinnercircleplzzzzzz​

Answer 1

Answer:

hey mate here is your answer

Answer 2

Answer:

$\color {blue} {r=14}$

Step-by-step explanation:

Ratio of radius = 4:9

Area of circle

$\pi {r}^{2}$

let the unknown radius be r itself.

$\pi {(21)}^{2} \\ 441\pi \\ 441 \times \frac{22}{7} \\ 63 \times 22 \\ = 1386 \: c {m}^{2}$

Let area of inner circle be 4x

Let area of outer circle be 9x

$9x = 1386 \\ x = 154$

Area of inner circle =

$4 \times 154 \\ = 616$

$\pi {r}^{2} = 616 \\ \frac{22}{7} {r}^{2} = 616 \\ {r}^{2} = 616 \times \frac{7}{22} \\ {r}^{2} = 28 \times 7 \\ {r}^{2} = 196 \\ r = \sqrt{196} \\ r = 14$