Multiplying Fractions by Whole Numbers — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A cookie recipe uses 3/4 cup of sugar per batch. Lin makes 4 batches on Monday and 2 more batches on Tuesday. How much sugar does she use in all?
A) 9/4 cups, which is 2 1/4 cups
B) 18/4 cups, which is 4 1/2 cups
C) 6/4 cups, which is 1 1/2 cups
D) 12/4 cups, which is 3 cups
Grade 4: 4 + 2 = 6 batches; 6 x 3/4 = 18/4 = 4 1/2 cups.
2. Each lap around a track is 2/5 mile. If Aaron runs 7 laps and Beth runs 3 laps, how many miles do they run together?
A) 20/5 miles, which is 4 miles
B) 10/5 miles, which is 2 miles
C) 7/5 miles, which is 1 2/5 miles
D) 15/5 miles, which is 3 miles
Grade 4: 7 + 3 = 10 laps; 10 x 2/5 = 20/5 = 4 miles.
3. A craft project uses 5/6 foot of ribbon. Mia has 4 feet of ribbon. After completing 4 projects, how much ribbon did she use?
A) 9/6 feet, which is 1 1/2 feet
B) 5/24 foot
C) 20/6 feet, which is 3 1/3 feet
D) 16/6 feet, which is 2 2/3 feet
Grade 4: 4 x 5/6 = 20/6 = 3 1/3 feet.
4. A water bottle holds 3/8 liter. If a class of 8 students each drinks one full bottle, how much water do they drink in all?
A) 11/8 liters, which is 1 3/8 liters
B) 3/64 liter
C) 8/8 liter, which is 1 liter
D) 24/8 liters, which is 3 liters
Grade 4: 8 x 3/8 = 24/8 = 3 liters.
Part B: Fill in the Blank
Write the correct answer on each line.
1. If 4 + 2 batches each use 3/4 cup of sugar, the total sugar used is 18/4 cups as an improper fraction.
Grade 4: 6 x 3/4 = 18/4.
2. Aaron and Beth run 7 + 3 = 10 laps of 2/5 mile each, totaling 20/5 miles.
Grade 4: 10 x 2/5 = 20/5 = 4 miles.
3. Mia uses 4 x 5/6 = 20/6 feet of ribbon for 4 projects, before simplifying.
Grade 4: 4 x 5/6 = 20/6 feet.
4. Eight bottles of 3/8 liter each give a total of 24/8 liters as an improper fraction.
Grade 4: 8 x 3/8 = 24/8 = 3 liters.
5. If each step is 2/3 meter and a path has 9 steps, the path length is 18/3 meters as an improper fraction.
Grade 4: 9 x 2/3 = 18/3 = 6 meters.