Question

The circumference of a circle is equal to the sum of the circumferences of 4 circles of radio 2.1cm,3.1cm,4.1cm,5.1cm. find the radius of new circle
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Answer 1

r1= 2.1 cm

r2= 3.1cm

r3 = 4.1cm

r4 = 5.1 cm

let be radius of new circle = R

circumference of circle = sum of circumference of 4 circle

2πR = 2π r1 + 2π r2 +2π r3 + 2π r4

2πR = 2π ( r1 + r2 +r3 +r4 )

on both side 2π will cut

R = 2.1 + 3.1 + 4.1 +5.1

R = 14.4