Question

A sum of Rs 1440 is lent out in three parts in such a way that the interests on first part at 2% for 3 years, second part at 3% for 4 years and third part at 4% for 5 years are equal. Then the difference between the largest and smallest sum is 

(a) Rs 400 

(b) Rs 560 

(c) Rs 460 

(d) Rs 200

Answer 1

(b) Rs 560.

Let the three parts be Rs x, Rs y and Rs z. Then,

\(\frac{x\times2\times3}{100}\) = \(\frac{y\times3\times4}{100}\) = \(\frac{y\times4\times5}{100}\)

∴ Largest share = x = \(\frac{50\times48}{3}\) = Rs 800

Smallest share = z = 5 × 48 = Rs 240 

Required difference = Rs 800 – Rs 240 = Rs 560.