Certa pessoa entra na igreja e diz a um santo: se você dobrar a quantia de dinheiro que eu tenho, dou-lhe R$ 20 000,00. Dito isto, o santo realizou o milagre, e a pessoa, o prometido. Muito animada, ela repetiu a proposta, e o santo, o milagre. Feito isto, esta pessoa saiu da igreja sem qualquer dinheiro. Pergunta-se: quanto em dinheiro a pessoa possuía ao entrar na igreja?
Google translation:
A person enters the church and says to a saint: if you double the amount of money I have, I will give you R $ 20,000.00. That said, the saint performed the miracle, and the person, the promised. Very excited, she repeated the proposal, and the saint, the miracle. That done, this person left the church without any money. The question is: how much money did the person have when entering the church?
Let the amount of money she came to church with =a
2*a - $20,000 =b - for balance..........(1)
2*b - $20,000 =0...............................(2)
Solve for (1) and ( 2):
a = $15,000 - The amount she came to church with
Check: 2 * $15,000 - $20,000 =$10,000
2 * $10,000 - $20,000 =$0
