Identify n and k in the following problem: There are 35 boys trying out for football in the fall. The coach only has 20 spots to fill on the roster. How many ways can he fill the remaining spots?
n=35 k=20
What are the numbers in the 3rd row of Pascal's Triangle?
1,3,3,1
Compute C(16,10)
8,008
16!/(6!10!) or (16*15*14*13*12*11*10*9*8*7)/10!
Identify n and k in the following problem: The school board has seven members, the board must have a chairperson, an assistant chairperson, and a secretary. How many different sets of these officers can be formed from this board?
n=7 k=3
If I wanted to expand the binomial (a+b)25, what row of Pascal's triangle would give me the coefficients?
The 25th row.
Solve P(8,2)
56
A) When does order matter? B) When does order not matter?
A) Permutations B) Combinations
Explain order matters:
What is where each object or value holds a certain place value in an arrangement.
Identify n and k the following Ten band directors at a summer band camp are planning to give a performance. One of the pieces they want to play calls for a Flute, an oboe, a bassoon, and a clarinet. Each of the band directors can play all four instruments. How many different quartets can they have?
n=10 k=4
C(7,2) will tell me.....
(there are 3 different possible answers!)
a) the number of ways to choose 2 items out of 7 (combination)
or b)the value in the 7th row, 2nd entry on Pascal's triangle
or c) the coefficient on the a5b2 term for (a+b)7
What are two ways to calculate a permutation?
Using P(n,k):
Multiplication principle: n*(n-1)*(n-2)*.... for k terms
or n!/(n-k)!
Identify n and k in the following problem: How many ways can you deal a five card hand from a standard deck?
n=52 k=5
(a+b)4 = 1a4 + 4a3b+ ____a2b2 + 4_____+ 1_____
In order:
6 (can be found out by doing C(4,2) or 4th row 2nd entry on PT)
ab3
b4
There are 53 band students going on a fieldtrip, how many ways can the director choose two student leaders for the bus ride?
1,378
1.76x1011 or 175,760,000,000 (assuming all letters and numbers can be repeated.)
Define what 6! means.
Multiply all integer values starting at 6 and going down to 1.
6*5*4*3*2*1
Identify n and k in the following problem:
The counseling department has to make appointments for planning meetings. Mr. Loomis has 125 students, and he can make an appointment every half hour between 8 and 2pm.
n= 125 k=12
How can you calculate C(100, 3), and where is that same answer located on Pascal's triangle?
C(100,3) = (100*99*98)/3!
or 100!/(3!97!)
The same value will be found in row 11, entry 3.