The average monthly expenditure of a family for the first four months is Rs 2,750, for the next three months is Rs 2,940 and for the last five months Rs 3,130. If the family saves Rs 5,330 during the whole year, find the average monthly income of the family during the year.
Choose the correct choice:
A) Rs 3,800  B) Rs 3,500  C) Rs 3,400  D) Rs 4,200  E) None of these
Average monthly expenditure of 4 months   = Rs 2,700   Total expenditure for 4 months = Rs 2,700 x 4   = Rs 11,000   Average monthly expenditure of 3 months   = Rs 2,940   Total expenditure of 3 months = Rs 2,940 x 5   = Rs 8,820   Average monthly expenditure of 5 months   = Rs 3,130   Total expenditure of 5 months = Rs 31,020   = Rs 1,560   Total expenditure in the whole year   = Rs 11,000 + 8,820 - Rs 15,650 = Rs 35,470.   Saving during the whole year = Rs 5,330.   Total income of the family during the year= Rs 35,470 + Rs 5,330 = Rs 40,800.   Therefore, Average monthly income during the year 40800/12 = Rs 3,400.   ANSWER:Rs 3,400
<result>C</result>
The average monthly expenditure of a family for the first four months is Rs 2,750, for the next three months is Rs 2,940 and for the last five months Rs 3,130. If the family saves Rs 5,330 during the whole year, find the average monthly income of the family during the year.