Log in to add a comment

## Answers

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.

This is an example of Combination.

Combination is the number of ways of selecting r items from a set of n.

Thus, the formula of Combination is

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

There are 8C5 ways that a student can answer 5 out of 8 questions.

Let's solve this.

8C5 = 8!/5!(8-5)!

= 8! / 5!(3!)

= (8×7×6×5!) / (5!×3×2×1)

= (8×7×6) / (3×2×1)

= 336 / 6

8C5 = 56 ways

Therefore, there are 56 ways that a student can answer 5 out of 8 questions.

Combination is the number of ways of selecting r items from a set of n.

Thus, the formula of Combination is

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

There are 8C5 ways that a student can answer 5 out of 8 questions.

Let's solve this.

8C5 = 8!/5!(8-5)!

= 8! / 5!(3!)

= (8×7×6×5!) / (5!×3×2×1)

= (8×7×6) / (3×2×1)

= 336 / 6

8C5 = 56 ways

Therefore, there are 56 ways that a student can answer 5 out of 8 questions.

The formula is:

C=

where:

n=total number o objects

r=number of objects you need to answer

Substitute:

C=

C=

Cancel out the 6 and the 3! since they have the same value, and then cancel out 5! on both sides since they are the same, then you are left with:

C=8x7

C=56

Hope this helps =)