816 Math Blog

I am not exactly sure how to borrow, but I will try my very best to do this.

My first question is 3 1/4 - 1 1/2 = ?

First we are going to find the lowest common denominator.
3 1/4 1 1/2
3 1/4 1 2/4

You can subtract 1 from 3, but you can't subtract 2/4 from 1/4. So you have to make the 1/4 bigger by borrowing 1 whole or in this case 4/4.
3-1=2
4/4 + 1/4= 5/4
2 + 5/4 = 2 5/4

Now we solve!
2 5/4 - 1 2/4
2-1=1
5/4 - 2/4 = 3/4
1= 3/4 = 1 3/4


The next question is 50 1/10 - 25 4/5=.

First we find the lowest common denominator.
1/10 4/5
1/10 8/10

50 1/10 - 25 8/10
Now you can take away 25 from 50, but you can't take away 1/10 from 8/10 so you have to make the 1/10 bigger by borrowing 1 whole or in this case 10/10.

50-1=49
1/10 + 10/10= 11/10
49 11/10 - 25 8/10
49 - 25 = 24
11/10 - 8/10 = 3/10
24 + 3/10 = 24 3/10