Add 21/84 and 20/72
21/84 + 20/72 is 19/36.
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,
21/84 = 21 × 6/84 × 6 = 126/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
126/504 + 140/504 = 126 + 140/504 = 266/504 - 266/504 simplified gives 19/36
- So, 21/84 + 20/72 = 19/36
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