QUIZ 2: PERMUTATIONS

Which expression represents the number of circular permutations of n things? n! (n - 1)! n!/(n - 1)!

(n - 1)!

How many permutations exist of the letters a, b, c, d taken two at a time? 12 8 2

12

282,240 21 14

14

6 9 18

18

0 2 undefined

2

How many permutations exist of the letters a, b, c, d taken four at a time? 24 12 4

24

How many permutations exist of the letters a, b, c, d taken three at a time? 24 12 4

24

5,040 30 16

30

How many different ways could a baking contest be judged if 15 pies are entered and 4 ribbons are awarded? 50,625 32,760 24

32,760

IT IS THE SAME THING!

35

3!3! = 362,880 81 36

36

1. the product of all the natural numbers from an integer down to one circular permutation 2. the indicated sum of the terms of an associated sequence factorial 3. an order of elements of a set series 4. an ordering of elements in a circle

4 1 2 3

If the general term of a sequence is 4, then the sequence is 4, 8, 12, 16, . . . 4, 16, 64, 216, . . . 4, 4, 4, 4, . . .

4, 4, 4, 4, . . .

How many different ways could eight students sit in a semicircle to watch an experiment? 40,320 5,040 8

40,320

What is the general term for the sequence 1,6,11,16,...? n + 5 5n - 4 5n + 1

5n-4

How many different ways can a family visit Philadelphia, Baltimore, and Washington? 3 6 12

6

How many different colored flags can be made from 10 colors of cloth if each flag is to consist of 3 different stripes? 1,000 120 720

720

How many different gardens can a farmer plant if he wants one row each of six vegetables? 720 120 36

720

How many different ways could seven birds perch around a circular bird bath? 5,040 4,320 720

720