What is the average period for calculating the interest on drawing if a partner withdraws drawings of an equal amount in the middle of every quarter?

6 months

The correct answer is option 4- 6 months.

Ist drawing = 15 May
So, months left after ist drawing is 10.5.

Last drawing = 14 Feb
So, months left after last drawing is 1.5.

Average period = (Time left after 1st drawing + Time left after last drawing) / 2
                       = (10.5 + 1.5)/2
                       = 12/2
                       = 6 months