1. Permutations
COURSE 2 LESSON 12-6
Find the number of permutations of the letters T, I, G, E, and R.
Use the counting principle.
5  4  3  2  1 = 120
first
letter
second
third
fourth
fifth
There are 120 different permutations.
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2. Permutations
COURSE 2 LESSON 12-6
How many different ways can you arrange a nickel, a dime, a penny, and a quarter in a row?
4! = 4  3  2  1 = 24
ways
to place
coins
first
coin
second
third
fourth
You can make 24 different arrangements of the coins.
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3. Permutations
COURSE 2 LESSON 12-6
Find the number of permutations for the blue, red, and green ribbons for 12 horses at a show.
There are 12 possible horses that can win the blue ribbon. After that, there are 11 horses that can win the red ribbon. Finally, there are 10 horses that can win the green ribbon.
12  11  10 = 1,320
blue
ribbon
red
green
Use the counting
principle.
There are 1,320 different ways that horses could win blue, red, and green ribbons.
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4. Permutations
COURSE 2 LESSON 12-6
1. Find the number of permutations for the letters A, B, C, and D.
2. Find the value of 5!.
3. Write the number of permutations in factorial form of the letters U, N, I, T, E, and D.
4. Find the number of three-letter permutations of the letters E, N, O, U, G, and H. 24
120 6!
120
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