4th Grade Multiplying a Fraction by a Whole Number Quiz: 10 Questions with Explanations

A \(3 \times \frac{1}{4}\)B \(4 \times \frac{1}{3}\)C \(3 + \frac{1}{4}\)D \(3 \times 4\)

Three fourths is 3 pieces of one fourth, so it is \(3 \times \frac{1}{4}\).

A \(\frac{4}{20}\)B \(\frac{4}{5}\)C \(\frac{5}{4}\)D \(\frac{1}{20}\)

Multiply the numerator: \(4 \times 1\) = 4. The denominator stays 5.

A \(3 \times \frac{2}{5} = \frac{5}{5}\)B \(3 \times \frac{2}{5} = \frac{6}{5}\)C \(3 \times \frac{2}{5} = \frac{6}{15}\)D \(3 \times \frac{2}{5} = \frac{5}{10}\)

There are 3 groups of 2 fifths, which is 6 fifths. The denominator is not multiplied.

A \(\frac{15}{40}\)B \(\frac{8}{13}\)C \(\frac{15}{8}\)D \(\frac{3}{40}\)

\(5 \times 3\) = 15 eighths. Multiplying the denominator by 5 is the common mistake.

A 12B 8C 4D 3

\(6 \times 2\) = 12 thirds, and 12 thirds is 4 wholes. Forgetting the denominator gives 12.

A \(\frac{6}{4}\)B \(\frac{12}{4}\)C \(\frac{3}{12}\)D \(\frac{9}{4}\)

Each jump is \(\frac{3}{4}\), so the jumps land at \(\frac{3}{4}\), \(\frac{6}{4}\) and \(\frac{9}{4}\).

A \(\frac{14}{10}\)B \(\frac{9}{10}\)C \(\frac{14}{20}\)D \(\frac{7}{20}\)

\(2 \times 7\) = 14 tenths. Adding 2 to the numerator gives 9.

A \(4 \times \frac{1}{9}\)B \(9 \times \frac{1}{4}\)C \(9 + \frac{1}{4}\)D \(9 \times 4\)

Nine fourths is 9 copies of one fourth.

A \(\frac{7}{4}\) cupsB \(\frac{3}{16}\) cupC \(\frac{12}{16}\) cupD 3 cups

\(4 \times \frac{3}{4}\) = \(\frac{12}{4}\) = 3 cups. The denominator stays 4.

A \(3\frac{1}{3}\) milesB \(\frac{10}{15}\) mileC \(\frac{7}{3}\) milesD \(3\frac{2}{3}\) miles

\(5 \times \frac{2}{3}\) = \(\frac{10}{3}\), which is 3 \(\frac{1}{3}\) miles.