Question

find the radius of a cylender whose volume is given to be 100 cm3 and height is 20 cm​

Answer 1

Given :

• Height = 20 cm
• Volume of cylinder = 100cm³

To find :

• radius

Solution :

Using formula

$v = \pi \: r {}^{2} h$

Putting the values

$100 = \frac{22}{7} \times r {}^{2} \times 10 \\ \frac{100}{10} \times \frac{7}{22} = r {}^{2} \: \: \: \: \: \: \: \: \: \\ \frac{10 \times 7}{22} = r {}^{2} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \frac{70}{22} = r {}^{2} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \frac{35}{11} = r {}^{2} \\ r {}^{2} = 3.18 \\ r = \sqrt{3.18}$

The radius is √3.18