Finish the line: “Multiply the whole, then…”
add it quick
What is the reciprocal of 3⁄4?
4/3
Multiply 2/3×3/4
1/2
4/5÷2/5
2
Convert 3 1/4 to an improper fraction.
13/4
In the chant, what do we “keep” and what do we “change” when converting mixed to improper fractions?
Keep the bottom (denominator), change the top (numerator).
True or False: The reciprocal of a whole number is always less than 1.
False (e.g., reciprocal of 2 is ½, which is less than 1, but reciprocal of ½ is 2, which is greater than 1).
1 1/2 X 2/5
3/5
3/4÷1/8
6
Convert 11/4 to a mixed number.
2 3/4
According to the chant, what do we do to the second fraction when dividing?
Flip it (find the reciprocal).
Find the reciprocal of 5
1/5
Multiply 5/6×3/10 and simplify.
1/4
2 1/2÷5 6/2
3
Convert 5 2/3 to an improper fraction and multiply by 2/5 give the answer as a mixed number.
17/3×2/5=34/15=2 4/15
In Keep, Change, Flip what do we change?
The division to multiplication.
Explain why we use reciprocals when dividing fractions.
Dividing by a fraction is the same as multiplying by its reciprocal, which makes the calculation easier.
What are the step‑by‑step guide for multiplying two mixed numbers, using the example. A: Example: 2 1/3×1 1/2
Convert to improper: 7/3×3/2
Multiply tops: 7 × 3 = 21
Multiply bottoms: 3 × 2 = 6
Simplify: 21/6=3 1/2
Explain “Keep, Change, Flip” and solve 7/8 ÷ 2/3
Keep first fraction, change ÷ to ×, flip second fraction. 7/8×3/2=21/16=1 5/16
Explain why we “keep the bottom, change the top” when converting a mixed number to an improper fraction. Include an example.
The denominator stays the same because the size of each part doesn’t change. Multiply the whole number by the denominator to find how many parts are in the wholes, then add the numerator for the extra parts. Example: 2 3/5 (2 × 5) + 3 = 13 parts 13/5
Use the multiply chant to solve: 2 1/2×4/5
Convert 2 1/2 to 5/2, multiply top × top = 20, bottom × bottom = 10, 20/10=2
Solve: 7/8÷14/5 using reciprocals.
7/8×5/14 = 35/112 = 5/16
A recipe calls for ¾ cup of sugar. You make 2⅔ batches. How many cups did you use?
= 2 cups.
Write a word problem for 5/6÷1/4, solve, and explain.
Example problem: A 5⁄6‑metre ribbon is cut into pieces 1⁄4 metre long. How many pieces? Solution: 5⁄6×4 =20/6=3 2/3 pieces. It makes sense because each piece is smaller than 1 metre, so more than 1 piece fits
A student converts 2 3/5 to 5/3 Explain the mistake and show the correct conversion.
They flipped the numbers instead of converting properly. Correct: (2 × 5) + 3 = 13, denominator stays 5 → 13/5