Sides of parallelogram is in the ratio 4 : 3 and its area is 462 units.  Altitude on greater side is 21 units , then altitude on the other side will be?

14 units 16.5 units 21 units 28 units

28 units

For this parallelgram DE, DF are two altitudes ; Let AB = 4R and BC = 3R and DE = 21 Area of parallelgram = base × height ⇒ AB × DE = BC × DF ⇒ 4R × 21 = 3R × DF ⇒ 4 × 21 = 3 × DF ⇒ DF = 28