Math
posted by Mary .
A man goes into a store and says, " If you give me as much money as I have with me now, I will spend $10.00 in your store." The proprietor agrees, and the man spends the money. He goes into a second store and again says, "If you give me as much money as I have now, I will spend $10.00 in your store." Again, the proprietor agrees, and the man spends the money. In a third store, he repeats his proposition, the proprietor agrees, and the man spends the money. At this point, the man has no money left. How much money did this man have to begin with? Explain your answer.

Try $8.75
One way to get the answer is to work the problem backwards. He must have had $5 when entering the third store. How much would he have had when entering the second store? Call that x.
x + x  10 = 5
x = $7.50
Now do it one more time. 
After spending1/3 of his money,a man has Rs 70 left. How much money did he have first