The task is to generate the correct answer for a given math problem.

[Q]: Problem: the cost of the paint is rs . 50 per kg . if 1 kg of paint covers 20 sq . ft , how much will it cost to paint outside of a cube having 20 feet each side
[A]: rs . 6000


[Q]: Problem: the average of first 22 natural numbers is ?
[A]: 11.5


[Q]: Problem: if the simple interest on a certain amount in at 4 % rate 5 years amounted to rs 1920 less than the principal . what was the principal ?
[A]:
240