An investor receives total of Rs. 5,700 per annum in interest from 3 stocks yielding 4 %, 5% and

Question

8% per annum respectively. The amount at 4% is Rs. 20,000more than the amount invested at
5%, and the interest from the 8% investment is 8 times the interest from the 5 % investment.
Amount of money invested in each stock is:

Answer 1

amount invested at 5% ---- x
amount invested at 4% = x+20000
amount invested at 8% = y

total interest is 5700
.05x + .04(x+20000) + .08y = 5700 , each term times 100
5x + 4x + 80000 + 8y = 570000
9x + 8y = 490000

interest from 8% = .08y
interest from 5% = .05x

" the interest from the 8% investment is 8 times the interest from the 5 % investment."
----> .08y = 8(.05x)
8y = 40x
y = 5x

sub into the first equation:
9x + 8(5x) = 490000
49x = 490000
x = 10,000
then y = 50,000

amount invested at 4% = 30,000
amount invested at 5% = 10,000
amount invested at 8% = 50,000

I will leave it up to you to verify that the answers are correct.