Multiplying Fractions
In word problems with fractions, the word "of" tells us we have to do what?
Multiply.
What strategy do we have to use when we divide fractions?
KEEP CHANGE FLIP!
When you multiply mixed numbers, what do you have to do first?
Turn the mixed numbers into improper fractions. (Texas Two Step)
1) Turn the mixed numbers into improper fractions.
2) Keep Change Flip.
Chelsea has 9 problems to do for math homework. She has solved 2/3 of the problems already. How many of her math problems has she solved?
6 problems
How do we turn whole numbers into improper fractions?
Put a 1 under it.
1/2 divided by 4/7
7/8
2 2/3 * 4 1/10
10 14/15
3 5/9 divided by 3
1 5/27
A cupcake recipe calls for 3/4 of a cup of butter. Rob wants to make 1/3 of the original recipe. How many cups of butter will Rob need?
1/4 cup
3/7 * 7/10
3/10
4/5 divided by 2/3
1 1/5
2 1/5 * 1 3/4
3 17/20
2 divided by 3 4/5
10/19
A relay race covers 1 1/2 miles, and each runner on a team will run 1/4 of a mile. How many runners are needed for a team?
6 runners
8/9 * 3/10
4/15
3/8 divided by 9/10
5/12
1 1/4 * 9
11 1/4
1/9 divided by 1 1/3
1/12
A recipe for 1 batch of cookies calls for ⅔ cups of raisins. Amy made 2½ batches of cookies. How many cups of raisins did she use in her recipe?
1 2/3 cups
2/3 * 5
3 1/3
2/5 divided by 4
1/10
1 5/7 * 2 1/2
4 2/7
1 6/7 divided by 5 3/4
52/161
1 7/8 miles