Q.Find the banker's discount and the proceeds on a bill of ₹6,000 that has 4 months still to run, discounted at 6% per annum.

Convert the 4 months to a fraction of a year, then charge simple interest on the face value.

Here $F = 6000$, $r = 6\%$, and $t = \dfrac{4}{12} = \dfrac{1}{3}$ year.

Banker's discount:

Proceeds:

$F - BD = 6000 - 120 = 5880.$ …

Treating 4 months as $t = 4$ years, or rounding $\tfrac{1}{3}$ carelessly before multiply …