A happy Frenchman was traveling in Russia. He took some money with him and came to a restaurant. He borrowed the same amount of money from the owner of the restaurant and spent one rouble. With the rest of the money, he went to the second hotel, where he borrowed the same amount of money and spent one rouble. Then he went to the third and fourth hotels and did the same thing, When he came out of the fourth restaurant, he had nothing left. How much did the cheerful Frenchman have?

A happy Frenchman was traveling in Russia. He took some money with him and came to a restaurant. He borrowed the same amount of money from the owner of the restaurant and spent one rouble. With the rest of the money, he went to the second hotel, where he borrowed the same amount of money and spent one rouble. Then he went to the third and fourth hotels and did the same thing, When he came out of the fourth restaurant, he had nothing left. How much did the cheerful Frenchman have?

Do you want money back? Do you want money for dinner? If not,
1. When he comes to a restaurant, he borrows the same amount of money from the owner of the restaurant, and then spends one rouble. At this time, he has money: a + A-1 = 2a-1
2. He went to the second hotel, where he borrowed the same amount of money he had with him, and then spent one rouble. At this time, he had money:
2（2A-1）-1=4A-3
3. He went to the third Hotel, where he borrowed the same amount of money he had with him, and then spent one rouble. At this time, he had money:
2（4A-3）-1=8A-7
4. He went to the fourth Hotel, where he borrowed the same amount of money he had with him, and then spent a ruble. At this time, he had money:
2（8A-7）-1=16A-15=0
A = 15 / 16 from above