How many ways can a committee of 3 people be chosen out of 7 people? |
70 35 210 840 |
35 |
The correct answer is Option (2) → 35 1. The Combination Formula The number of ways to choose $k$ items from a set of $n$ items is given by: ${n \choose k} = \frac{n!}{k!(n-k)!}$ 2. Substitute the Values Here, $n = 7$ (total people) and $k = 3$ (people to be chosen): ${7 \choose 3} = \frac{7!}{3!(7-3)!} = \frac{7!}{3! \times 4!}$ 3. Simplify the Calculation Expand the factorials: ${7 \choose 3} = \frac{7 \times 6 \times 5 \times 4!}{ (3 \times 2 \times 1) \times 4!}$ The $4!$ in the numerator and denominator cancel each other out: ${7 \choose 3} = \frac{7 \times 6 \times 5}{6}$ ${7 \choose 3} = 7 \times 5 = \mathbf{35}$ Conclusion There are 35 different ways to form the committee. |