Investing Gives You So Many Perks | FinShort#81

Welprint Ltd. has given you the following information: Calculate cash flow from Investing Activities on the basis of the above information.

A retired person has Rs 70,000 to invest and two types of bonds are available in the in the market investment. First type of bond yields an annual income of 8% on the amount investment invested and second type of bond yields 10% per annum. As per norms, he has to invest minimum in the first type and not more than 30,000 in the second type. How should investment, so as to get maximum returns, after one year of investment?

A sum of money becomes 3 times of itself in 6 years at compound interest. In how many years will it become 81 times?