Question

11. The diameters of three circles are in the ratio
3:5: 6. If the sum of the circumferences of
these circles be 308 cm; find the difference
between the areas of the largest and the
smallest of these circles.

plz send me a pic of the working attached to your answer​

Answer 1

Ratio of radii = 3:5:6

radii=3x,5x/6x

circumference=2 πr

2πx3x+2πx5x+2πx6x=308

= 6πx +10πx +12πx=308

28πx=308

x =308/28π =308x7/28x22=3.5

radii-3x,5x, 6x

= 10.5, 17.5, 21cm

Area of largest circle=πr^2

= 22x21^2/7=1386cm2

Area of smallest circle = πr 2

= 22x10.5^2/7=346.50cm2

Difference of area b/w largest and smallest circle=1039.50cm2