There are 48 people in class one, 15 out of 16 in class two and 9 out of 10 in class three. How many people are there in class three?

There are 48 people in class one, 15 out of 16 in class two and 9 out of 10 in class three. How many people are there in class three?

Class 2 = 48 × 15 / 16 = 45 persons
Class 3 = 45 △ 9 / 10 = 50 people

There are 48 students in class 6-2. The number of boys is three fifths of that of girls. How many boys and girls are there in class 6-2?
Don't have this (1 + 3 / 5), because I can't understand it

Three fifths means that the number of female students is divided into five on average, and three of them are male students. If there are eight (5 + 3) students in the class, then there are 48 students in the class, and each one is six. Then the number of male students is 6 * 3 = 18, and that of female students is 6 * 5 = 30