Mr x opens a recurring deposit account of Rs 300 at 8%interest p.a. if the maturity amount is Rs 9930,find the period for which he continued with the account .

Asked by saketagarwal.dbl | 27th Mar, 2017, 02:22: PM

Expert Answer:

begin mathsize 16px style Let space the space period space be space straight n space months.
straight P space equals space Rs. space 300
straight R equals 8 percent sign space straight p. straight a.
rightwards double arrow Interest space equals space straight P cross times fraction numerator straight n left parenthesis straight n plus 1 right parenthesis over denominator 2 cross times 12 end fraction cross times straight r over 100
rightwards double arrow Interest space equals space 300 cross times fraction numerator straight n left parenthesis straight n plus 1 right parenthesis over denominator 2 cross times 12 end fraction cross times 8 over 100
rightwards double arrow Interest space equals space straight n left parenthesis straight n plus 1 right parenthesis
Since space money space deposited plus Interest equals Maturity space Value
rightwards double arrow 300 cross times straight n plus straight n left parenthesis straight n plus 1 right parenthesis equals 9930
rightwards double arrow straight n left parenthesis 300 plus straight n plus 1 right parenthesis equals 9930
rightwards double arrow straight n left parenthesis 301 plus straight n right parenthesis equals 9930
rightwards double arrow straight n left parenthesis 301 plus straight n right parenthesis equals 30 left parenthesis 301 plus 30 right parenthesis
rightwards double arrow straight n equals 30
Hence comma space the space period space is space 30 space months. end style

Answered by Rebecca Fernandes | 27th Mar, 2017, 05:55: PM