Add 21/81 and 60/80
21/81 + 60/80 is 109/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 80 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 81 × 80 = 6480,
21/81 = 21 × 80/81 × 80 = 1680/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
60/80 = 60 × 81/80 × 81 = 4860/6480 - Add the two like fractions:
1680/6480 + 4860/6480 = 1680 + 4860/6480 = 6540/6480 - 6540/6480 simplified gives 109/108
- So, 21/81 + 60/80 = 109/108
In mixed form: 11/108
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