Question

40. If the diameters of two circles are 12 cm and 16 cm, then the diameter of the cincle having area equal to the sum of areas of the two circles is (@) 24 cm (b) 18 cm (c) 20 cm (d) 15 cm​

Answer 1

Step-by-step explanation:

Correct option is

D

20cm

Let radius of new circle be R

Radius of first circle =

2

16

=8 cm

Area of first circle =π×r

2

=64π cm

2

Radius of second circle =

2

12

=6 cm

Area of second circle =π×r

2

=36π cm

2

Area of new circle =64π+36π

πR

2

=100π

R

2

=100

R=

100

=10cm