1. I have two 6-sided dice. One is numbered 1-6, and the other is numbered 5-10.

 

What is the probability that when I roll them I will get...

+ 1 2 3 4 5 6
5 6 7 8 9 10 11
6 7 8 9 10 11 12
7 8 9 10 11 12 13
8 9 10 11 12 13 14
9 10 11 12 13 14 15
10 11 12 13 14 15 16

What is the most likely sum? 11

2. Josh, Sarah, Kelly and Brian had these dice

Josh: 2, 2, 2, 2, 6, 6
Sarah:3, 3, 3, 3, 3, 3
Kelly: 4, 4, 4, 4, 0, 0
Brian: 1, 1, 1, 5, 5, 5

a. If Josh and Sarah both roll their dice, who will have the higher number more often? What is the probability Josh will have the higher number?

larger J or S? 2 2 2 2 6 6
3 S S S S J J
3 S S S S J J
3 S S S S J J
3 S S S S J J
3 S S S S J J
3 S S S S J J

Sarah's die will be higher more often. The probability that Josh's die is higher is 12/36=1/3

b. If Josh and Sarah both roll their dice, and they add the numbers, what is the probability that the sum will be:

+ 2 2 2 2 6 6
3 5 5 5 5 9 9
3 5 5 5 5 9 9
3 5 5 5 5 9 9
3 5 5 5 5 9 9
3 5 5 5 5 9 9
3 5 5 5 5 9 9

 

c. If Sarah and Kelly both roll their dice, who will have the higher number more often? What is the probability that Sarah will have the higher number?

Sarah:3, 3, 3, 3, 3, 3
Kelly: 4, 4, 4, 4, 0, 0

larger S or K? 4 4 4 4 0 0
3 K K K K S S
3 K K K K S S
3 K K K K S S
3 K K K K S S
3 K K K K S S
3 K K K K S S

Kelly's die will be higher more often. The probability that Sarah's die is higher is 12/36=1/3

d. If Kelly and Brian both roll their dice, who will have the higher number more often? What ist he probability that Brian will have the higher number?

Kelly: 4, 4, 4, 4, 0, 0
Brian: 1, 1, 1, 5, 5, 5

larger K or B? 4 4 4 4 0 0
1 K K K K B B
1 K K K K B B
1 K K K K B B
5 B B B B B B
5 B B B B B B
5 B B B B B B

Brian's die will be larger more often. The probability that Brian's die is higher is 24/36=2/3

e. If Kelly and Brian both roll their dice, and they add the numbers, what is the probability that the sum will be:

+ 4 4 4 4 0 0
1 5 5 5 5 1 1
1 5 5 5 5 1 1
1 5 5 5 5 1 1
5 9 9 9 9 5 5
5 9 9 9 9 5 5
5 9 9 9 9 5 5

f. If Brian and Josh both roll their dice, who will have the higher number more often? What is the probability Brian will have the higher number?

Josh: 2, 2, 2, 2, 6, 6
Brian: 1, 1, 1, 5, 5, 5

larger J or B? 2 2 2 2 6 6
1 J J J J J J
1 J J J J J J
1 J J J J J J
5 B B B B J J
5 B B B B J J
5 B B B B J J

Josh will have the higher number more often.

The probability that Brian's number is higher is 12/36=1/3

g. Put the dice in order so that person 1 beats person2, person 2 beats person 3, person3 beats person 4 but person 4 beats person 1 (see page 539#6)

Josh is higher more often compared to Brian; Brian's die is higher more often to Kelly. Kelly's die is higher more often compared to Sarah. Sarah's die is higher more often compared to Josh