Question

The aggregate monthly expenditure of a family was $Rs.18720$ during the first $3$ months, $Rs.20340$ during the next $4$ months and $Rs.21708$ during the last $5$ months of a year. If the total savings during the year be Rs. find the average monthly income of the family.

Answer 1

The aggregate yearly expenditure of a family $=Rs(18720\times 3)+Rs(20340\times 4)+Rs(21708\times 5)$
$=Rs.(56160+81360+108540)$
$=Rs.246060$
The total savings during the year $=Rs35340$
Therefore the yearly income $=Rs246060+Rs35340$
$=Rs.281400$
$\therefore$ The average monthly income of the family $=\frac{281400}{12}=Rs.23450$
Hence, The average monthly income of the family is $Rs.23450$.