Adding and Subtracting Fractions with unlike denominators and multiplying fractions
Hi friend! I am Mary. I have a few guests coming over, so I thought to bake some cookies. The recipe calls for 12 cup of brown sugar and 34 cup of white sugar. Let’s calculate the total amount of sugar I need?
Firstly, we ensure that the fractions to be added must have a common denominator. In our case, the denominators are unlike and consequently, we will make an equivalent fraction. Let’s start working:
x 2
12 = 24
x 2
Now, the newly produced fraction for brown sugar and the quantity for white sugar are expressed with the common denominator of 4, and can easily be added i.e. 24 + 34 = 2+34
Hence the total amount of sugar needed is 4.
Ready to work with some other fractions?
Now, this one is be a bit tricky: 14 + 15 .
If we go through the list of the multiples of both denominators, 4 and 5, we get to know that 20 is the least common number.
14 = 520
15 = 420
Can u add or even subtract these two fractions now? Easy? A few more to practice
Well done! You have mastered the skill of adding and subtracting fractions. Let’s learn something about multiplying fractions. Here is how you do.
Example: 23 x 16 = Numerator x NumeratorDenominator x Denomiantor = 2 x 13 x 6 = 218
Can you simplify this fraction further?
A few more to become a champion!
18 x 45
56 x 37
14 x 25
