Mensuration Practice Test 4

According to the statement,
2πr = 2(21l + b) .......(i)
Now area of the circle = $\mathit{\pi }{\mathit{r}}^2$ = $5544\mathit{c}{\mathit{m}}^2$
${\mathit{r}}^2$ = $\frac{5544\times 7}{22}$ = $\frac{38808}{22}$
${\mathit{r}}^2$ = 1764
r = 42 cm
Substituting the value of r in equation (i)
$2\times \frac{22}{7}\times 42$ = 2 (2 (40 + b))
264 = 160 + 4b
104 = 4b
b = 26 cm
Now area of the rectangle = l × b
= 40 × 26
= 1,040 $\mathit{c}{\mathit{m}}^2$