There are 15 light bulbs of which 5 are defective. In how many
ways can six light bulbs with exactly one defective be chosen?
C(15,6)
C(10,5)*C(5,1)
P(10,5)*P(5,1)
P(15,6)
How many ways are there to fill out a 25 question multiple
choice exam if there are 5 ways to answer each question?
255
525
C(25,5)
P(25,5)
How many nonnegative solutions (xi >=0 for
1<=i<=3) does the equation x1 + x2 +
x3 = 10 have?
103
C(10,3)
C(12,2)
310