Sumi wants to invest atmost Rs. 20,000 in VIII sereis National Savings Bonds and Kisan vikash Oathras. According to rules, she has to invest atleast Rs. 5000 in saving bonds and atmost Rs. 8000 in Kisan Pathra. If the rate of inerest on savings bond is 10% p.a and the rate of Kisan vikash Pathara is 15% p.a, how much money should she invest in each to ear maximum yearly income ? also find the maximum yearly income.

You have Rs.12,000/- saved amount, and wants to invest it in two schemes yielding 10% and 15% interest. How much amount should be invested in each scheme so that you should get overall 12% interest.

Jinal saves Rs.1600 during the first year, Rs. 2100 in the second year, Rs. 2600 in the third year, If she continues her saving in this pattern, in how many years will she save Rs. 38,500?

A retired person wants to invest an amount upto Rs 20,000. His broker recommends investing in two types of bonds A and B, bond A yielding 10% return on the amount invested and bond B yielding 15% return on the amount invested. After some consideration he decides to invest atleast Rs 5,000 in bond A and not more than Rs 8,000 in bond B. He also wants to invest atleast as much in bond A as in bond B. How should he invest to maximise his return on investment?