UTMA Probability 2

Question 1

A card is drawn from a standard 52-card deck. What is the probability of drawing a king?

Accepted Answer

1/13

Answer

There are 4 kings in 52 cards: P = 4/52 = 1/13.

Question 2

If P(A) = 0.5, P(B) = 0.4, and P(A and B) = 0.2, what is P(A or B)?

Accepted Answer

0.7

Answer

P(A∪B) = P(A) + P(B) − P(A∩B) = 0.5 + 0.4 − 0.2 = 0.7.

Question 3

In how many ways can 3 items be chosen from 7 (order does not matter)?

Accepted Answer

35

Answer

C(7,3) = 7!/(3!×4!) = (7×6×5)/(3×2×1) = 35.

Question 4

Two events A and B are independent. If P(A) = 0.3 and P(B) = 0.5, what is P(A and B)?

Accepted Answer

0.15

Answer

For independent events: P(A∩B) = P(A) × P(B) = 0.3 × 0.5 = 0.15.

Question 5

A box has 3 defective and 7 non-defective bulbs. What is the probability of drawing 2 non-defective bulbs in a row (without replacement)?

Accepted Answer

7/15

Answer

P = (7/10) × (6/9) = 42/90 = 7/15.

UTMA - University of Toronto Math Assessment Practice Test