Question

12 students of class IX took part in GK quiz. If the number of boys is 4 more than the number of girls. Find the number of boys and girls took part in the quiz ?
A) 7, 5
B) 9, 3
C) 8, 4
D) 6, 6

Answer 1

Clearly, we have :

B-3 = E ...(i)

B + 3 = D ...(ii)

A+B = D + E+10 ...(iii)

B = C + 2 ...(iv)

A+B + C + D + E= 133 ...(v)

From (i) and (ii), we have : 2 B = D + E ...(vi)

From (iii) and (vi), we have : A = B + 10 ...(vii)

Using (iv), (vi) and (vii) in (v), we get:

(B + 10) + B + (B - 2) + 2B = 133 ⇔ 5B = 125 ⇔ B = 25.

Answer 2

12 students of class IX took part in GK quiz. If the number of boys is 4 more than the number of girls. Find the number of boys and girls took part in the quiz ?
A) 7, 5
B) 9, 3
C) 8, 4
D) 6, 6

Answer: C) 8, 4

Explanation:

Let the number of girls be x.
Let the number of boys be x + 4.

°•° x + x + 4 = 12

Or, 2x + 4 = 12

Or, 2x = 12 - 4

Or, 2x = 8

Or, x = 8/2

•°• x = 4

No. Of girls = x = 4

No. of boys = x + 4 = 4 + 4 = 8