Question

radius of circle is 5 find circumference of circle whose arra is49 times of the given circle

Answer 1

first take out the value of x and put it u will get answer

Answer 2

$radius = 5cm \\ area \: of \: this \: cirlce = \pi {}^{2} \\ = \frac{22}{7} \times 5 \times 5 = \ \frac{550}{7} m {}^{2} \\now \: area \: of \: the \: circle \: whose \: perimeter \: is \\ = 49 \times \frac{550}{7} \\ = 3850 {m}^{2} \\ let \: the \: radius \: be \: r \\ \pi \times r \times r = 3850 {m}^{2} \\ {r}^{2} = 3850 \times \frac{7}{22} \\ {r}^{2} = 1225 {m}^{2} \\ r = \sqrt{1225 {m}^{2} } \\ r = 35 {m}^{2} \\ hence \: circumference \: of \: the \: cirlce \\ = 2 \times \frac{22}{7} \times 35m \\ = 220m$