Add 72/80 and 20/81
72/80 + 20/81 is 929/810.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
72/80 = 72 × 81/80 × 81 = 5832/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
20/81 = 20 × 80/81 × 80 = 1600/6480 - Add the two like fractions:
5832/6480 + 1600/6480 = 5832 + 1600/6480 = 7432/6480 - 7432/6480 simplified gives 929/810
- So, 72/80 + 20/81 = 929/810
In mixed form: 1119/810
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