A person closer his account in an investment scheme by withdrawing ? 10000. One year ago, he had withdraw ? 6000. Two years ago, he had withdrawn ? 5000. Three years ago, he had not withdrawn any money. How much money had he deposited approximately at the time of opening the account 4 yr ago, if the annual simple interest is 10%?

Suppose the person had deposited ? P at the time of opening the account .
? After one year he had P + (P x 10 x 1)/100 = ? 11P/10

After two years, he had
11P/10 + (11P/10 x 10 x 1)/100 = ? 121P/100 ...(i)

After withdrawn ? 5000 from ? 121P/100, the balance
= ? (121P - 500000)/100

After 3 yr, he had
(121P - 500000)/100 + [(121P - 500000)/100 x 10 x 1]/100
= 11(121P - 500000)/100 ... (ii)

After withdrawn ? 6000 from amount (ii) the balance
= (1331P/1000 - 11500)

? After 4 yr, he had ? (1331P - 5500000)/1000 + 10% of ? (1331P - 5500000)/1000
= ? (11/10) x (1331P/1000 - 11500) ... (iii)

After withdrawn ? 10000 from amount (iii) the balance =0
? 11/10(1331P/1000 - 11500) - 10000 = 0
? P = ? 15470