18 students of a class took part in a quiz. If the number of girls is 8 more than the number of boys, find the product of the number of boys and girls.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 65.
Let the number of girls and number of boys in the class be x and y respectively.
According to the given question,
x + y = 18 ....(i)
And x - y = 8 ...(ii)
Adding the equations (i) and (ii),
⇒ 2x = 26
⇒ x = 13
Subtracting equations (i) and (ii),
⇒ 2y = 10
⇒ y = 5
Now, the required product = x × y
⇒ 13 × 5 = 65
Hence the product of the number of boys and girls is 65.