Question

# The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. The ratio of the surface areas of the balloons in two cases is(a) 1:4  (b) 1:3  (c) 2:3  (d) 1:2

Solution

## In First case, the radius of the balloon =6 cmIn Second case, the radius of the balloon =12 cm.Now, Surface Area of a hemisphere =3π(radius)2So, the ratio of the surface area's will be =3π(6)2:3π(12)2=62:122=36:144=1:4Hence, the correct option is (a)MathematicsSecondary School Mathematics IXStandard IX

Suggest Corrections

3

Similar questions
View More

Same exercise questions
View More

People also searched for
View More