5.3I Multiply Whole Numbers by Fractions

We can restate the problem 2/3 x 5 as "2/3 of 5." For instance, if we have 5 pounds of sugar and we only need 2/3 of it, how could we think about that? We would find 2/3 of 5 by multiplying 2/3 x 5.

What is 2/3 of 5 pounds of sugar?

• 7/3

• 7/4

• 3 1/3

• 11/3

Multiplication is combining equal groups. If we want to find out how much flour we need for three cookie recipes, we can multiply what we need for one batch by 3. If we need 3/4 cup of flour for one recipe, then we would say we need 3 groups of 3/4 cup of flour. What is 3 x 3/4?

• 2 1/4

• 4/9

• 6/4

• 9/12

16 x 3/5

• 9 2/5

• 8 8/5

• 9 3/5

• 19/5

Tags

CCSS.3.NF.A.1

CCSS.3.OA.A.1

CCSS.3.OA.A.3

9 x 5/6

Remember to change your answer to a mixed number and simplify your fraction (if possible).

• 45/54

• 2 1/2

• 7 1/2

• 7 5/6

3/10 x 7

Be careful how you write this down... some of you were confused before the break. This is 3/10 times 7.

• 3/70

• 2 1/10

• 21/70

• 10/10 or 1 whole

Terrance runs 5 miles each week. His brother runs 5/6 the distance Terrance runs in one week. How far does Terrance's brother run in one week?

• 3 1/3 miles

• 4 1/6 miles

• 5 1/6 miles

• 4 miles

Katana has a shelf that is 5 feet long. She wants to paint a design along 7/10 of the shelf. How many feet of the shelf will Katana paint a design?

• 1 2/5

• 1 1/5

• 3 1/2

• 4 3/10

Carly mixes vinegar and baking soda for a science project. She has a spoon that measures 1/4 teaspoon. If she fills the spoon 6 times with baking soda, which expression will help her figure out how much baking soda she will have in the mixture?

• $6\ +\frac{1}{4}$

•  $6\ \div\frac{1}{4}$

• $6\ -\ \frac{1}{4}$

• $6\ \times\frac{1}{4}$

Margo was helping clean up after a class party. There were 3 boxes remaining with pizza in them. Each box had 3/8 of a pizza left. How much pizza was left in all?

• 1 1/8 pizza

• 8/9 of a pizza

• 1 3/8 pizza

• No pizza because Margo secretly ate the rest while the teacher wasn't looking.

Doug has 33 feet of rope. He wants to use 2/3 of it for his canoe. How many feet of rope will he use for his canoe?

• 66 feet

• 22 feet

• 33 feet

• 11 feet