Question

In a school, all students play either Chess or Carom or both. 400 play Carom, 150 play Chess, and 130 play both games. Find the number of students who play Chess only.

Answer 1

To find the number of students who play only Chess, we can use the principle of set theory.

Let's denote:
- \( C \): the number of students who play Carom
- \( H \): the number of students who play Chess
- \( B \): the number of students who play both games

From the given data:
- \( C = 400 \) (students who play Carom)
- \( H = 150 \) (students who play Chess)
- \( B = 130 \) (students who play both games)

We want to find the number of students who play only Chess. This can be calculated using the following formula:

\[
\text{Students who play only Chess} = H - B
\]

Substituting the values:

\[
\text{Students who play only Chess} = 150 - 130 = 20
\]

Therefore, the number of students who play only Chess is **20**.