Add 42/84 and 20/72
42/84 + 20/72 is 7/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
42/84 = 42 × 6/84 × 6 = 252/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
252/504 + 140/504 = 252 + 140/504 = 392/504 - 392/504 simplified gives 7/9
- So, 42/84 + 20/72 = 7/9
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