Puzzle

Fun with  Mathematics

Puzzle

A smart boy used to play computer game ‘ Free cell’  every day  before he used his laptop for assigned work. The percentage of win is displayed after the game is over.The fraction in the percentage is not considered by the computer.. He aimed 100 % win but he scored only 50 % after playing 300 games.

To make it to be 51% how many wins successively  he has to score?  He was unable to win all the games then played. If he got this 51 % after playing 20 games , then how many games he won in 20 ?.

Answer

In the beginning games he won 150 out of 300.  Suppose he played x games and won in all the games,

Then the new winning percentage becomes  150 + x/(300 +x) = 51/100 .X must be at least 7.

In the additional 20 games he won x games to make  the winning percentage 51. Then

150+x /320 = 51/100  , x must be 14.