Question

Evaluate 7C3 OA) 25 O B) 45 OC) 35 OD) 20

Answer 1

Answer:

C) 35

Step-by-step explanation:

$^7C_3 \\ = \frac{7!}{3!(7 - 3)!} \\= \frac{7!}{3! \: 4!} \\ = \frac{7 \times 6 \times 5 \times 4!}{3 \times 2 \times 1 \times 4!} \\ = \frac{7 \times 6 \times 5 \times 4!}{3 \times 2 \times 1 \times 4!} \\ = 35 \\ \huge \red{ \boxed{ \therefore \: ^7C_3 = 35}}$

Answer 2

Answer:

C=35

Step-by-step explanation:

⁷C₃

These is combination

using the rule it states that

ⁿCₐ= n!/(n-a)!a!

so therefore ⁷C₃= 7!/(7-3)!3! = 7!/4!3!=7x6x5x4x3x2x1/{(4x3x2x1)x(3x2x1)}

4x3x2x1 cancels itself as it appears up and down

7x6x5/6

6 cancels each itself as it appears up and down

7x5 = 35