Factorial, Permutation and Combination

Four students need to be selected from a class

of 15 to help clean up the campus. How many different ways can the 4 students be chosen?

• 32 760

• 60

• 1 365

A Mathmatics test contains five different questions labeled A, B, C, D, and E. You are supposed to choose 2 to answer. How many different ways are there to do this?

• 5

• 10

• 15

A disc jockey has to choose three songs for the last few minutes of his evening show.  If there are nine songs that he feels are appropriate for that time slot, then how many ways can he choose and arrange to play three of those nine songs?

• 84

• 504

• 9!

• 3!

A student has to answer 8 questions in a 10-question test. If she has to answer at least 3 questions of the first 4, in how many ways can she select the questions?

• 44

• 45

• 39

• 24

In a Permutation the order of the outcomes ​ ​ (a)   , but in a Combination the order​ (b)  

• matters

• doesn't matter

Ten students in your math class are presenting unique proofs to their classmates.  The order in which the proofs are chosen to be presented is random.   Find the probability that the proof using the HL Theorem is chosen first and your proof on CPCTC Theorem is chosen to go second.  

• 1/10

• 1/10!

• 4/5

• 1/90

How many ways can 8 runners finish in the top 3 places where the prizes for 1^st, 2^nd, and 3^rd are all different and matter?

Mathematical Equivalence

ON

Calculate ₈P₂

Mathematical Equivalence

OFF

A family of 3 plans to sit in the same row at a movie theater. How many ways can the family be seated in 3 seats?

• 3

• 6

• 1

A group of 8 swimmers are swimming in a race. Prizes are given for first, second, and third place. How many different outcomes can there be?

• 336

• 56

• 24