Add 42/72 and 30/81
42/72 + 30/81 is 103/108.
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,
42/72 = 42 × 9/72 × 9 = 378/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
30/81 = 30 × 8/81 × 8 = 240/648 - Add the two like fractions:
378/648 + 240/648 = 378 + 240/648 = 618/648 - 618/648 simplified gives 103/108
- So, 42/72 + 30/81 = 103/108
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