Classical Probability and Complements Practice

You roll a fair six-sided die once. What is the probability of rolling an odd number?

3/6, which simplifies to 1/2 (the favorable outcomes are 1, 3, and 5).

A standard deck contains 52 cards with 4 aces. What is the probability of drawing an ace at random?

4/52, which simplifies to 1/13.

A box holds 20 raffle tickets numbered 1 through 20. What is the probability of drawing a ticket divisible by 5?

4/20, which simplifies to 1/5 (tickets 5, 10, 15, and 20).

Using the same box of 20 tickets numbered 1 through 20, what is the probability of drawing a ticket that is not divisible by 5?

1 - 1/5 = 4/5 (or 16/20 simplified to 4/5).

You spin a spinner divided into 8 equal sections numbered 1 to 8. What is the probability of landing on a number less than 3?

2/8, which simplifies to 1/4 (sections 1 and 2).

A bag contains 5 green tiles, 3 blue tiles, and 2 yellow tiles. What is the probability of picking a tile that is not blue?

7/10 (Total tiles = 10; non-blue tiles = 5 + 2 = 7, or 1 - 3/10 = 7/10).

A fair coin is tossed three times, giving 8 equally likely outcomes. What is the probability of getting at least one head?

7/8 (The complement is TTT, which has probability 1/8. 1 - 1/8 = 7/8).