Aashish withdrew Rs. 10,000 per month from the firm for his personal use during the year ending March 31, 2017. What will be the amount of interest if the amount is withdrawn at the beginning of each month and rate of interest on drawings is 8% per annum?

When equal amounts are withdrawn at the beginning of each month, interest needs to be calculated using the average time period.

Given Information:

• Monthly withdrawal = Rs. 10,000
• Number of months = 12
• Rate of interest = 8% per annum
• Timing = Beginning of each month

Total Drawings = Rs. 10,000 × 12 = Rs. 1,20,000

For drawings made at the beginning of each month, the average time period is calculated as:

Average Period = $\frac{n + 1}{2}$ months, where n = number of months

Average Period = $\frac{12 + 1}{2}$ = $\frac{13}{2}$ = 6.5 months

Interest on Drawings = Total Drawings × Rate × Time (in years)

Interest = Rs. 1,20,000 × $\frac{8}{100}$ × $\frac{6.5}{12}$

Interest = Rs. 1,20,000 × 0.08 × $\frac{6.5}{12}$

Interest = Rs. 9,600 × $\frac{6.5}{12}$

Interest = Rs. $\frac{62,400}{12}$

Interest = Rs. 5,200

The formula uses (n+1)/2 instead of n/2 because when amounts are withdrawn at the beginning of each month, they remain with the partner for one additional month compared to withdrawals made at the end of each month.