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CBSE Class 9 Answered

The radius of a spherical balloon increases from 7 cm to 14 cm as air is pumped into it. Find the ratio of surface areas of the balloon in two cases.
Asked by Topperlearning User | 04 Jun, 2014, 01:23: PM
answered-by-expert Expert Answer

Original surface areas S1 = 4

New surface area S2 =

Answered by | 04 Jun, 2014, 03:23: PM

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CBSE 9 - Maths
find the radius of a sphere whose area is 154 cm
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CBSE 9 - Maths
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CBSE 9 - Maths
If the area of the top of a hemispherical bowl is 154 cm2. Its volume is 714.65 cm3(app.)  718.67 cm3 (app.) 716.92 cm3 (app.) 720.46 cm3 (app.)
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CBSE 9 - Maths
A hemispherical bowl is made of steel, 0.7 cm thick has inner radius 14 cm. It is to be polished from inside and outside. Calculate the total area to be polished.
Asked by Topperlearning User | 18 Oct, 2017, 02:56: PM
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CBSE 9 - Maths
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Asked by Topperlearning User | 18 Oct, 2017, 03:03: PM
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