What will be the difference between the interest on a sum of Rs.2,000 at 7% per annum for 3 years and that on a sum of Rs.3,200 at 6% per annum for 2 years?

Rs.36

Interest = \(\frac{Principal ×Rate × Time }{100}\)

Interest at Rs 2000 at 7% in 3 years ( I_{1 )} =  \(\frac{2000 ×7 × 3}{100}\)= Rs  420

Interest at Rs 3200 at 6% in 2 years ( I₂  ) = \(\frac{3200 ×6× 2}{100}\)= Rs  384

∴  I_{1  -} I₂   =   Rs 420 - Rs 384  =  Rs 36