Question

1. Two dice are thrown at the same time . What is the probability that the sum will be 7 or 11 ?

2. A ball is drawn at random from a box containing 6 red balls , 4 white balls and 5 blue balls.
Determine the probability that is red or white.​

Answer 1

1. 0.2222222

2. .6667

Explanation:

for question 1

there can only be 36 outcomes so you find out how many time you could get 7and2 which is 8 from so u write 8.36=.2222

for question 2

divide the outcome by the total out comes example(there are 6 red balls and 4 white out of 15 so you do 10/15=.6667)

Answer 2

#1

Outcomes with sum of 7:

• 1 + 6, 2 + 5, 3 + 4, 4 +3. 5 + 2, 6 + 1

Outcomes with sum of 11:

• 5 + 6, 6 + 5

Total outcomes:

• 6*6 = 36

Required probability:

• P(sum of 7 or 11) = (6 + 2)/36 = 8/36 = 2/9 or 22.22%

#2

• P(red or white) = (6 + 4)/(6 + 4 + 5) = 10/15 = 2/3 or 66.67%