Correct Answer - Option 1 : 1 : 4

**Given**

Radius of two cylinders = 2 : 1

Volume of two cylinders are equal

**Formula used**

Volume of cylinders = πr^{2}h

Where r and h are radius and height of cylinders respectively

R/r = 2/1

**Calculation**

πR^{2}h = πr^{2}H

Where R, h, r and H are radius and height of two cylinders respectively

R^{2}/r^{2 }= H/h

(2/1)^{2} = H/h

4/1 = H/h

h/H = 1/4

h : H = 1 : 4

**The ratio of heights of two cylinders is 1 : 4**