Question

Calculate Average Due date from the following information (Assume February of 28 days).

Date of the bill	Term	Amount $Rs.$
August 10, 2011	3 months	6,000
October 23, 2011	60 days	5,000
December 4, 2011	2 months	4,000
January 14, 2012	60 days	2,000
March 08, 2012	2 months	3,000

Assume that the due date is 3 days after the completion of the term.
A). Jan 1, 2012
B). Aug 10, 2011
C). Feb 28, 2012
D). Aug 30, 2011

Answer 1

Hint: For answering this question, first we will calculate the due date for each bill and then assume a base date and calculate the average due to date, we will use the following formula:
$\text{Average due date=base date+}\dfrac{\text{total amount}}{\text{total product}}$
Let us first calculate the due date for each of the bills in the table. The calculations are as follows for the due date that is the starting date of the bill+ term + 3 days that is done as follows:
(i). August 10, 2011 + 3 Months + 3 Days = September 13, 2011.
(iI). October 23, 2011 + 60 Days + 3 Days = December 25, 2011.
(iii). December 4, 2011 + 2 Months + 3 Days = February 7, 2012.
(iv). January 14, 2012 + 60 days + 3 Days = March 18, 2012.
(v). March 08, 2012 + 2 Months + 3 Days = May 11, 2012.

Complete step-by-step solution
Here, we are assuming September 13, 2011, as a base date because it is the date that comes first.

Due date	Amount Rs.	No.of days away from the due date	Product of amount and no.of due days away
September 13, 2011	6,000	0	0
December 25, 2011	5,000	103	515000
February 7, 2012	4,000	147	588000
March 18, 2012	2,000	186	372000
May 11, 2012	3,000	240	720000
Total	20,000		2195000

Let us now calculate the average due date that is $\Rightarrow $ $\text{Average due date=base date+}\dfrac{\text{total amount}}{\text{total product}}$​\[\]
Substitute total amount =2195000 and total product = 20000
$\begin{align}
& \Rightarrow \text{Average due date=september 13,2011+}\dfrac{2195000}{20000}\dfrac{2195000}{20000} \\
 & \Rightarrow \text{Average due date=september 13,2011}+109.75 \\
 & \Rightarrow \text{Average due date=january 01,2012} \\
\end{align}$
Hence, the average due date is January 01, 2012. Hence, option (A) is correct.

Note: Here while answering this question we should be careful while counting the due dates if we just skip a date we will end up having a completely different answer. For example, if we assume that we had counted the due date of (ii) one wrong as December 26, 2011, we will have all the values varied so the total amount will be 2,200,000 the average date will also be varied. We will end up having a completely wrong answer.