Question

The area of
circular tinplate is 38.5 m square . finds it circumference

Answer 1

Given that Area of a circular tin plate = 38.5 m^2.

                           $\pi$r^2 = 38.5m^2

                          r^2 = 38.5/$\pi$

                          r^2 = 38.5/22/7

                          r^2  = 38.5 * 7/22

                          r^2  = 12.25.

                           r = 3.5cm.


We know that circumference = 2$\pi$r

                                                  = 2 * 22/7 * 3.5

                                                  = 22cm.


Therefore the circumference of the circular tin plate = 22cm.


Hope this helps!

Answer 2

area=πr^2
38.5= 22/7 r^2
38.5*7/22= r^2
49/4= r^2
7/2= r

cirmcumference= 2πr
= 2*22/7 *7/2
= 22m