Hi Paula,
I am going to start with two mixed fractions, change them to improper fractions and then add them. I want to start with 1 ^{3}/_{10} and 2 ^{1}/_{4} .
1 ^{3}/_{10} = ^{10}/_{10} + ^{3}/_{10} = ^{13}/_{10}
2 ^{1}/_{4} = ^{8}/_{4} + ^{1}/_{4} = ^{9}/_{4}
To add these fractions we need a common denominator. The denominators are 10 = 2 5 and 4 = 2 2, and hence the least common denominator is 2 2 5 = 20.
^{13}/_{10} = ^{26}/_{20} and ^{9}/_{4} = ^{45}/_{20}
Thus
1 ^{3}/_{10} + 2 ^{1}/_{4} = ^{13}/_{10} + ^{9}/_{4} = ^{26}/_{20} + ^{45}/_{20} = ^{71}/_{20}
Finally, 71 divided by 20 is 3 with a remainder of 11 so
1 ^{3}/_{10} + 2 ^{1}/_{4} = ^{71}/_{20} = 3 ^{11}/_{20}
Penny
