1. Solve:

6C3

120***?
720
20
240

is this right?

no -- 6*5*4 / 1*2*3 = 20

You calculated 6P3

oh, that's actually what i thought at first. i had a little debate.

anyway thank you!:)

for combinations:

n!/[r!(n-r)!]

6! /[ 3! (6-3)! ]

6*5*4/ (3*2*1)

To solve the expression 6C3, which represents the combination of choosing 3 items from a set of 6, we can use the formula for combinations:

nCr = n! / (r!(n-r)!)

Here, n represents the total number of items in the set, and r represents the number of items we want to choose.

Plugging in the values for our expression, we get:

6C3 = 6! / (3!(6-3)!)
= 6! / (3!3!)

Now, let's calculate the factorials:

6! = 6 × 5 × 4 × 3 × 2 × 1 = 720
3! = 3 × 2 × 1 = 6

By simplifying:

6C3 = 720 / (6 × 6) = 720 / 36 = 20

So, the answer to 6C3 is 20.

Out of the options provided, the correct answer is 20.