This 45-minute test has 8 questions worth 20 points. It covers counting, permutations, combinations, probability with counting, the multiplication rule and expected value. Show all work, and leave probabilities as exact fractions unless a decimal is requested.
- Grade: Precalculus
- Chapter: Counting, Permutations, Combinations and Probability
- Common Core: S-CP.B.8, S-CP.B.9, S-MD.A.1, S-MD.A.2
- Time: 45 minutes
- Total: 20 points (Question 1: 2 pts; Question 2: 2 pts; Question 3: 2 pts; Question 4: 3 pts; Question 5: 2 pts; Question 6: 3 pts; Question 7: 3 pts; Question 8: 3 pts)
Question 1: Counting routes (2 points)
A road map shows 3 roads from Home to the Mall and 4 roads from the Mall to the Beach.
- How many one-way routes lead from Home to the Beach through the Mall? (1 point)
- How many round trips are possible if any road may be used in either direction? (1 point)
Question 2: Permutations and combinations (2 points)
Evaluate each expression.
- \(_{9}P_{3}\) (1 point)
- \(_{9}C_{3}\) (1 point)
Question 3: Arranging letters (2 points)
Find the number of distinct arrangements of all the letters in BOOKKEEPER.
Question 4: Forming a team (3 points)
A club has 7 boys and 5 girls. A team of 4 is chosen.
- How many teams are possible? (1 point)
- How many teams have exactly 2 girls? (1 point)
- If the team is chosen at random, what is the probability that it has exactly 2 girls? (1 point)
Question 5: Three spades (2 points)
Three cards are dealt from a standard 52-card deck. Find the probability that all three are spades.
Question 6: Two draws (3 points)
A bag holds 6 white and 4 black marbles. Two marbles are drawn without replacement, as shown in the incomplete tree.
- Find the probability that both marbles are white. (1 point)
- Find the probability that the marbles are different colors. (2 points)
Question 7: Expected value (3 points)
The bar graph shows the probability distribution of a random variable \(X\). The probability for \(x=4\) is missing.
- Find \(P(X=4)\). (1 point)
- Find \(E(X)\). (2 points)
Question 8: Carnival game (3 points)
Liam pays $4 to draw one card from 20 cards. One card pays $30, four cards pay $5 each, and the other cards pay nothing. Find the expected net result per play and interpret it.
See every chapter on the Precalculus math page.



