Add 28/72 and 15/81
28/72 + 15/81 is 31/54.
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,
28/72 = 28 × 9/72 × 9 = 252/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
15/81 = 15 × 8/81 × 8 = 120/648 - Add the two like fractions:
252/648 + 120/648 = 252 + 120/648 = 372/648 - 372/648 simplified gives 31/54
- So, 28/72 + 15/81 = 31/54
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