Probability - William Stettler

Which of these numbers cannot be a probability?

-0.12

Suppose a voter poll is taken in three states. In state A, 50% of voters support the liberal candidate, in state B, 60% of the voters support the liberal candidate, and in state C, 35% of the voters support the liberal candidate. Of the total population of the three states, 40% live in state A, 25% live in state B, and 35% live in state C. Given that a voter supports the liberal candidate, what is the probability that she lives in state B?

0.32

A card is drawn at random from a deck of cards. Find the probability of getting a queen

1/13

A die is rolled, find the probability that an even number is obtained.

1/2

Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?

1/2

In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green?

1/3

What is the probability of getting a sum 9 from two throws of a dice, given that one of the die is a 5?

1/3

A card is drawn at random from a deck of cards. Find the probability of getting the 3 of diamond.

1/52

What is the probability of getting a sum 9 from two throws of a dice?

1/9

A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn without replacement. What is the probability that none of the balls drawn is blue?

10/21

In a card game, suppose a player needs to draw two cards of the same suit in order to win. Of the 52 cards, there are 13 cards in each suit. Suppose first the player draws a heart. Now the player wishes to draw a second heart. Since one heart has already been chosen, there are now 12 hearts remaining in a deck of 51 cards.

12/51

In a lottery, there are 10 prizes and 25 blanks. A lottery is drawn at random. What is the probability of getting a prize?

2/7

A bag contains 4 white, 5 red and 6 blue balls. Three balls are drawn at random from the bag. The probability that all of them are red

2/91

In a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected?

21/46

Out of 50 people surveyed in a study, 35 smoke in which there are 20 males. What is the probability the if the person surveyed is a male given that it is a smoker?

4/7

Two dice are tossed. The probability that the total score is a prime number

5/12

The blood groups of 200 people is distributed as follows: 50 have type A blood, 65 have B blood type, 70 have O blood type and 15 have type AB blood. If a person from this group is selected at random, what is the probability that this person has O blood type?

70 / 200 = 0.35

What is the Probability Formula?

P(A|B) = P(AandB)/P(B)

what are the two possible outcomes on coin? H (heads) and T (Tails).

{(H,T),(H,H),(T,H),(T,T)}

If you are rolling a dice, what is the sample space?

{1,2,3,4,5,6}

If you are flipping a coin, what is the sample space?

{head,tails}