Well, first of all, in mathematics, the word "of" represents multiplication. Also, when ever a number has the percentage sign(%). It means it is divided by 100.That is, its denominnator is 100. So in this case, 70% is 70/100. The questions says they won 70% OF the games. That simply means; 70/100×90 When you calculate that, you will get 63. Which means they won 63 of the games.Hope i helped. Have a nice day.