The curved surface area of cylinder X is 45% of the curved surface area of cylinder Y. If the volume of cylinder X is 27% of the volume of cylinder Y, then the height of cylinder X is what percentage of the height of cylinder Y?
The curved surface area of cylinder X is 45% of the curved surface area of cylinder Y. If the volume of cylinder X is 27% of the volume of cylinder Y, then the height of cylinder X is what percentage of the height of cylinder Y? Correct Answer 75%
Let the radius and height of cylinder X be ‘r’ units and ‘h’ units respectively
Let the radius and height of cylinder Y be ‘R’ units and ‘H’ units respectively
Given,
Curved surface area of cylinder X = 45% of Curved surface area of cylinder Y
⇒ 2πrh = (9/20) × (2πRH)
⇒ rh/RH = 9/20 ---(1)
Also,
Volume of cylinder X = 27% of Volume of cylinder Y
⇒ πr2h = (27/100) × (πR2H)
⇒ r2h/R2H = 27/100
Substituting from (1),
⇒ (r/R) × 9/20 = 27/100
⇒ r/R = 3/5
Substituting in (1),
⇒ (h/H) × 3/5 = 9/20
⇒ h/H = 3/4
⇒ h = (3/4) H
⇒ h = 75% of H
∴ Height of cylinder X is 75% of the height of cylinder Y