the average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of girls is 15.4 years. Find the ratio of the number of boys to the number of girls.
Answers
Answered by
23
Let the number of girls and boys be x and y respectively
Since, we're taking out the average age of the whole class, we will form an equation like-
(x* 16.4 + y * 15.4) / x+y = 15.8
16.4x + 15.4y / x+ y = 15.8
16.4x + 15.4y = 15.8 x + 15.8y (Multiplied x+y with 15.8)
16.4x - 15.8x = 15.8y - 15.4y
0.6 x = 0.4 y
So ratio will be 0.6/ 0.4 = 2/3
Answer = 2:3
Since, we're taking out the average age of the whole class, we will form an equation like-
(x* 16.4 + y * 15.4) / x+y = 15.8
16.4x + 15.4y / x+ y = 15.8
16.4x + 15.4y = 15.8 x + 15.8y (Multiplied x+y with 15.8)
16.4x - 15.8x = 15.8y - 15.4y
0.6 x = 0.4 y
So ratio will be 0.6/ 0.4 = 2/3
Answer = 2:3
Similar questions