Correct Answer - Option 4 : 36
Given:
The ratio of boys and girls in a group is 5 : 7.
Calculation:
Let the number of boys be 5y and number of girls be 7y.
⇒ (5y + 5)/(7y - 11) = 2/1
⇒ 5y + 5 = 14y - 22
⇒ 27 = 9y
⇒ y = 3
Total number of boys and girls = 5y + 7y= 12y = 12 × 3 = 36
∴ The total number of boys and girls initially in the group is 36.