Question

A copper wire, when bent in the form of a square, encloses an area of 484 cm2 . If the same wire is bent in the form of a circle, the radius of the circle will be
(1) 10 cm
(2) 14 cm
(3) 15 cm
(4) 21 cm

Answer 1

area of square

${a}^{2}$
a equals side length of square

area is given

find side length from area

calculate perimeter of the square to find the total length of the wire

perimeter of square equals 4a

then perimeter of circle equals perimeter of square

i.e.

2*pi*r = 4a

from the formula given above, find r

Answer 2

Ans=14 cm........
sry for some disturbance in the pic