7th Grade Probability and Probability Models Quiz: 10 Questions with Explanations

A \(0\)B \(1.2\)C \(\frac{1}{2}\)D \(0.99\)

Probabilities are between 0 and 1, so 1.2 is impossible.

A \(\frac{3}{7}\)B \(\frac{3}{10}\)C \(\frac{7}{10}\)D \(\frac{1}{3}\)

\(3 \div 10\). The total includes all marbles.

A \(\frac{1}{6}\)B \(\frac{2}{3}\)C \(\frac{1}{2}\)D \(\frac{1}{3}\)

5 and 6 are greater than 4: \(\frac{2}{6} = \frac{1}{3}\).

A \(0.35\)B \(0.14\)C \(2.86\)D \(0.26\)

\(14 \div 40 = 0.35\).

A \(0.8\)B \(0.2\)C \(0.\frac{2}{1}\)D \(1.2\)

\(1 – 0.2 = 0.8\).

A \(0.75\)B \(0.15\)C \(0.25\)D \(0.35\)

\(1 – 0.3 – 0.45 = 0.25\).

A 100B 25C 10D 50

Tails has probability 1/2, so about 50.

A Probability \(0.9\)B Probability \(0.5\)C Probability \(0.1\)D Probability \(0\)

A probability closer to 1 means more likely.

A ImpossibleB Unlikely but possibleC CertainD Likely

\(P(green) = \frac{4}{10} = 0.4\), which is a bit less than one half.

A The coin must be unfairB Probability changedC Chance variation in a small number of trialsD Tails must come next

With few trials, results vary. More tosses would be closer to 0.5.