Mini-Lesson: Decomposing Fractions & Multiplying Fractions by a Whole Number

Decomposing Fractions Unit Fraction – Fractions with a numerator of one. Fractions can be “decomposed” (separated into small parts) by using repeated addition: 4/5 = 1/5 + 1/5 + 1/5 + 1/5 How many times is 1/5 added together to equal 4/5? So, 4/5 = 4 x 1/5

Multiples Multiple – A multiple of a whole number is the product of that number and another number. Example: 15 is a multiple of 5, because 3 x 5 = 15. You can find the multiples of a number by skip counting: 5, 10, 15, 20, 25 . . . You can also find the multiples of unit fractions. The number line below is broken into sixths. What are the multiples of 1/6? 1 6 2 6 3 6 4 6 5 6 6

Multiple – A multiple of a fraction is the product of the unit fraction and a whole number. 1 6 2 6 3 6 4 6 5 6 6 or 1 Where would Freddy the Frog land if he made three jumps down the number line? Write this as a multiplication sentence. 3 x 1/6 = 3/6

Multiples Multiples go to infinity, so we can continue our counting pattern past 1 (and even further). 1 1 ½ 2 1 6 2 6 3 6 4 6 5 6 6 7 6 8 6 9 6 10 6 11 6 12 6 We can show 9 jumps on this number line as 9 x 1/6, which is equal to 9/6. This is the same as 1 ½

Practice Use a multiplication equation showing each fraction as a multiple of a unit fraction. 3/4 5/10 5/6 7/8 10/7

Exit Question Exit Question Charlie ate 1/4 of a pizza each day for 3 days. How much pizza did he eat in all? Draw a number line to represent this problem. Solve using repeated addition. Solve using multiplication.