Add 42/63 and 20/81
42/63 + 20/81 is 74/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 63 × 9 = 567,
42/63 = 42 × 9/63 × 9 = 378/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Add the two like fractions:
378/567 + 140/567 = 378 + 140/567 = 518/567 - 518/567 simplified gives 74/81
- So, 42/63 + 20/81 = 74/81
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