How Much Money A Person had Initially ? || Job Interview Puzzles

 Puzzle Details 

One person has some money in his pocket, He visits, four temples on the way. As soon as he visits any temple, the money in his pocket gets doubled and, on his way out, he donates Rs. 100 to each temple. in Total He visits four temples. After visiting the last temple, his pocket is empty of all the money, so how much money, he had initially?

Solution 

Let’s assume, a person began his quest with Rs. x.

in 1st Temple: As soon as he enters the temple, his money is doubled to 2x. On his way out he donates Rs. 100. Therefore, he is left with Rs. Rs. (2x – 100).

In 2nd Temple: As soon as he enters the temple, his money is doubled to 2(2x – 100). 2x – 100 is the money left before visiting the 2nd temple.  On his way out he donates another Rs. 100 and he is left out with Rs. (4x – 300)

3rd Temple: As soon as he enters the temple, his money is doubled to 2(4x – 300). 4x – 300 is the money left before visiting the 3rd temple. On his way out he donates another Rs. 100 and he is left with Rs. (8x – 700)

4th Temple: As soon as he enters the temple, his money is doubled to 2(8x – 700). 8x – 700 is the money left before visiting the 4th temple. On his way out he donates another Rs. 100 and he is left with Rs. (16x – 1500).

According to the question, after his last visit, he completely runs out of money.

Therefore,

=> 16x - 1500 = 0;

=> x = 1500/16;

=> x = 93.75

hence a person had started his quest with Rs 93.75 in his pocket.