Question

The ratio of boys and girls in a class is 1 :2. In new session, the number of boys
increased by 10 and the number of girls increased by X. Now, their ratio became 3:
4. Find the value of X.​

Answer 1

The value of X is 13

Step-by-step explanation:

From question, the ratio of boys and girls in a class = 1 : 2

The number of boys increases is 10 and the number of girls increased by X

Now, the ratio becomes:

⇒ (1 + 10) : (2 + X)

From question, the new ratio = 3 : 4

Now,

⇒ (1 + 10) : (2 + X) = 3 : 4

⇒ (1 + 10)/(2 + X) = 3/4

4(1 + 10) = 3(2 + X)

4(11) = 6 + 3X

44 - 6 = 3X

38 = 3X

X = 38/3

∴ X = 12.67 ≈ 13