The ratio of the number of boys to the number of girls in a school of 640 students, is 5 : 3. If 30 more girls are admitted in the
school, then how many more boys should be admitted so that the ratio of boys to that of the girls, becomes 14 : 9.
This questions was previously asked in
SSC CGL 3rd March 2020 Shift-1
Explanation:
- Initially, the ratio of boys to girls is 5:3.
- Total students (boys + girls) = 640.
- Let the number of boys be 5x and the number of girls be 3x.
- Therefore, 5x + 3x = 640, solving gives x = 80.
- Boys = 5 * 80 = 400, Girls = 3 * 80 = 240.
- 30 more girls join, making the total number of girls 270.
- We need the boys to girls ratio to be 14:9.
- If 'y' more boys are added, then (400 + y) / 270 = 14 / 9.
- Solving gives: 9(400 + y) = 3780, leading to 3600 + 9y = 3780.
- Simplifying: 9y = 180, so y = 20.
- Option 4: 20 is correct.
By: santosh ProfileResourcesReport error