College Algebra & Trigonometry, 2018a

7.2. FACTORIAL NOTATION AND PERMUTATIONS 315
20) How many ways can a president, vice president and secretary be chosen
from a group of 20 students?
21) How many ways can a president, vice president, secretary and treasurer
be chosen from a group of 50 students?
22) How many ways can 5 boys and 5 girls be seated in a row containing ten
seats:
a) with no restrictions?
b) if boys and girls must alternate seats?
23) How many ways can 5 boys and 4 girls be seated in a row containing nine
seats:
a) with no restrictions?
b) if boys and girls must alternate seats?
24) How many ways can 6 people be seated if there are 10 chairs to choose
from?
25) How many ways can 4 people be seated if there are 9 chairs to choose from?
26) How many ways can a group of 8 people be seated in a row of 8 seats if
two people insist on sitting together?
27) How many ways can a group of 10 people be seated in a row of 10 seats if
three people insist on sitting together?