Multiplying and Dividing Fractions


 

The Common Core State Standards covered in Unit 5  are:

  • Add and subtract fractions with unlike denominators, including mixed number

  • Multiply a whole number by a fraction

  •  Multiply a fraction by a fraction

  • Solve story problems involving multiplying a whole number of a fraction by a fraction

  • Demonstrate that an area of a rectangle with fractional side lengths can be found through tiling or by multiplying side lengths

  • Represent the product of two fractions as an array whose dimenstions are the two frations being multiplied

  • Compare the size of a product to the size of one of its factors on the basis of the size of the other factor, without performing the indicated multiplication

  • Explain why multiplying a given number by a fraction less than 1 results in a product smaller than the given number; explain why multiplying a given number by a fraction greater than 1 results in a product greater than the given number

  • Divide a unit fraction by a whole number; use a visual model to represent the division of a unit fraction by a whole number

  • Divide a whole number by a unit fraction; use a visual model to represent division of a whole number by a unit fraction

  • Solve story problems involving division of a unit fration by a whole number; and division of a whole number by a fraction









 Gary Paulsen was treating his dogs to pie, before he learned they shouldn't eat that.

He had 1/3 of a pie left and then cut it into 4 equal pieces to give to
Storm, Fred, Fonzie, and Cookie.

How much of the original pie did each dog get?




 Hawk is getting a new pen.

It is rectangular in shape and measures 1 3/4 yards long and 1/2 yard wide.

Hawk wants at least one square yard of pen.

Did Hawk get her wish?





Gary had a 9 yard long rope for one of his traplines.

How many pieces of rope can he cut from that piece if
he wants each piece to be 1/3 yard long?



Gary's wife is making a sign to encourage him in the Iditarod.

The sign is 1 1/3 yards wide by 2 1/3 yards long.

What is the area of the sign that Mrs. Paulsen makes for Gary?



Gary made a cushion for Storm.

The cushion is 3/4 yard long and 5/6 yard wide.

What is the area of the cushion?





 
 



All members of the dog club voted for their favorite dog.

Half voted for Storm, 1/4 voted for Cookie, 1/8 voted for Fonzie, 1/16 voted for Olaf, and the rest voted for Fred.

If 2 members voted for Fred, how many students belong to the dog club?


When Gary tests drives a sled, he does 1/5 backwoods sledding,
1/5 frozen lake sledding, and 3/5 sledding around his house.

If he sleds for 12 1/3 miles, how many miles are sledding around his house?



Decide true or false for each of the following statements.
* MEANS TO MULTIPLY
 3/4 * 5/12 = 5/16
7/8 * 4/5 = 11/40
5/6 * 4/7 = 10/21
1/3 * 2/3 = 2/6
3/5 * 1/3 = 1/5
 2/3 * 3/8 = 6/11
3/4 * 3/9 = 1/4 
5/8 * 2/5 = 7/13



Use the fractions in the table to answer questions 1-4.

Find two fractions to fit each description.

1/2    1/3    1/4    2/3    3/4

The product is 1/8, and the sum is 3/4.
Both the product and the difference are equal to 1/12.
The product is 1/2, and the difference is 1/12.
The product is 1/6, and the sum is less than 1.

 






Multiplying Fractions





Links from IXL Math


Estimating

Estimating products-whole numbers and unit fractions
Estimating products-whole numbers and fractions

Scaling Fractions and Whole Numbers
Scaling fractions with fractions
Scaling whole numbers with fractions

Multiplying Fractions and Whole Numbers
Multiply fractions and whole numbers I
Multiply fractions and whole numbers II
Multiply whole numbers and fractions-word problems

Multiplying Fractions
Multiply two fractions
Multiply two fractions-word problems
Multiply three or more fractions by fractions



Links from AAAMath.com


Multiply fractions-online practie
Multiplying fractions and whole numbers



More Practice Links

How to multiply fractions
How to multiply mixed fractions
Multiply fractions and whole numbers-online practice
Multiply fractions-online practice
Multiply fractions word problems


Dividing Fractions





Links from IXL Math

Divide a unit fraction by a whole number
Divide whole numbers by unit fractions
Divide fractions by whole numbers
Divide unit fractions by whole numbers-word problems
Divide whole numbers by unit fractions using models
Divide whole numbers by fractions



More Practice Links

Divide fractions by whole numbers-aaamath.com
Divide fractions by whole numbers-mathisfun.com
Divide whole numbers by fractions-mathgames.com
Divide fractions by whole numbers-mathgames.com
Divide fractions by whole numbers-problem solving




Area with Fractions


How to find the area of a rectangle using fractions-VIDEO
Practice finding the area of a rectangle from Khan Academy
Practice finding the area of rectangles-no fractions-game format




Unit 5 Games

Multiplying fractions-Math Soccer
Multiplying fractions-Millionaire Game
Fraction Jeopardy-all operations in this game
Can you multiply these?  From KIDSMATHTV
Dividing fractions basketball-challenging
Play fraction/decimal concentration game
Soccer Shootout-set games for fractions and set the difficulty



Time to Exercise the Brain

Daily Sudoku for Kids Brain Benders Play Rags to Riches
Ninja Primes and Composites
The Train Race Online Mankala
Who Wants to Win $1,000,000.00? Math Hunt Family Math Challenges
 What's the Best Way to get Paid?  Mystery Math Coin Flipping





   Links to the math sites that we love!

 

Great Help for Most Place Value Need help? Ask Dr. Math
Practice rounding with online flashcards Math Dictionary for Kids
Online Flashcards-all operations Tons of chances for practice-worksheets
Challenging Math Problems
A+ Math Games
Math Mania Challenges
Late Delivery-Great Algebra Practice
Mystery Math-How do they do that? Order of Operations
Cool Math-Interactive Activities
Math Baseball
Multiplication tips by kids Tesselations-Math is Fun!
The Fruit Game Math Playground