Add 70/72 and 21/81
70/72 + 21/81 is 133/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
70/72 = 70 × 9/72 × 9 = 630/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Add the two like fractions:
630/648 + 168/648 = 630 + 168/648 = 798/648 - 798/648 simplified gives 133/108
- So, 70/72 + 21/81 = 133/108
In mixed form: 125/108
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