Problem 72
There are two roads between towns \(\mathrm{A}\) and \(\mathrm{B}\). There are three roads between towns \(\mathrm{B}\) and \(\mathrm{C}\). How many different routes may one travel between towns \(\mathrm{A}\) and \(\mathrm{C}\).
Problem 73
How many ways can r different balls be placed in \(\mathrm{n}\) different boxes? Consider the balls and boxes distinguishable.
Problem 74
How many different numbers of 3 digits can be formed from the numbers \(1,2,3,4,5\) (a) If repetitions are allowed? (b) If repetitions are not allowed? How many of these numbers are even in either case?
Problem 76
Calculate the number of permutations of the letters \(\mathrm{a}, \mathrm{b}, \mathrm{c}, \mathrm{d}\) taken four at a time.
Problem 80
In how many ways may a party of four women and four men be seated at a round table if the women and men are to occupy alternate seats?
Problem 81
How many different sums of money can be obtained by choosing two coins from a box containing a penny, a nickel, a dime, a quarter, and a half dollar?
Problem 82
How many baseball teams of nine members can be chosen from among I twelve boys, without regard to the position played by each member?
Problem 83
How many "words" each consisting of two vowels and three consonants, can be formed from the letters of the word "lintegral"?
Problem 86
Of 37 men and 33 women, 36 are teetotalers. Nine of the women are non-smokers and 18 of the men smoke but do not drink. 13 of the men and seven of the women drink but do not smoke. How many, at most, both drink and smoke.
Problem 90
Find the probability of drawing a black card in a single random draw from a well-shuffled deck of ordinary playing cards.