Understand how to divide fractions by multiplying by the reciprocal.
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Introduce division as a missing multiplier.
You already know how to do simple division.
For example, what is ?
It is . But notice that this problem can be restated as a multiplication problem: What should be multiplied by 4 to get 12?
Clear algorithmic visualization showing the flip of the divisor.
Dividing by a fraction is the exact same as multiplying by its reciprocal.
Define reciprocal and provide Brahmagupta's rule.
To find the reciprocal of a fraction, swap its numerator and denominator. For the divisor , its reciprocal is .
Solve 2/3 divided by 3/5.
Problem.
Evaluate the following using Brahmagupta's formula:
Solve 3/4 divided by 1/7.
Let's evaluate step by step.
Step 1: Keep the dividend exactly as it is. Step 2: Change the division sign () to multiplication (). Step 3: Flip the divisor to its reciprocal, which is .
Finally, multiply the numerators together and the denominators together to get the final answer of .
Check understanding of division scaling.
What happens when you evaluate ?
Word problem involving division of fractions.
Leena made 5 cups of tea. She used litre of milk for this. How much milk is there in each cup of tea?
List the total volume of milk and the number of cups.
Write the expression to divide the total milk evenly.
Change the division to multiplication using the reciprocal of the divisor.
Show the multiplication of numerators and denominators.
State the final volume of milk per cup with units.