If you take 2/3c flour from a bowl containing 2 1/2c of flour, how much flour is left in the bowl?

Question

 Measurement

 

Answer 1

Hey there Mika,

To do this, you'll need to find the least common denominator of 

2/3 and 2-1/2

 

2-1/2 is also 5/2 

 

So if you want to find a common denominator for 2/3 and 5/2, the least common multiple of 3 and 2 (the two denominators) is 6:

 

Thus 2/3 becomes 4/6 because to get 6 in the denominator, you must multiply both the numerator AND denominator by 2:

 

2/3 * 2/2 = 4/6

 

Now, to get a 6 denominator for 5/2, we must multiply it by 3/3:

 

5/2 * 3/3 = 15/6

 

Now with a common denominator, we can do this:

 

15/6 - 4/6 (taking away the 2/3 cup of flour from the 2-1/2 cups of flour)

 

15/6 - 4/6 = 11/6 cups of flour

 

11/6 = 1-5/6 cups of flour are left in the bowl!