Of 132 examinees of a certain class, the ratio of passed to failed students is 9 : 2. If 4 more students passed, what would have been the ratio of passed to failed students?

1. 3 : 28

2. 28 : 5

3. 4 : 25

4. 25 : 4

Given,

Total examinees of a class = 132 and ratio of passed to failed = 9 : 2.

Let number of passed students be 9x and failed students be 2x.

Then,

⇒ 9x + 2x = 132

⇒ 11x = 132

⇒ x = $\dfrac{132}{11}$ = 12.

The number of passed students = 9 × 12 = 108

The number of failed students = 2 × 12 = 24

If 4 more students passed, then

New number of passed students = 108 + 4 = 112

New number of failed students = 24 - 4 = 20

Then the new ratio of passed to failed = 112 : 20 = 28 : 5.

Hence, option 2 is the correct option.