Add 20/84 and 21/72
20/84 + 21/72 is 89/168.
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,
20/84 = 20 × 6/84 × 6 = 120/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
120/504 + 147/504 = 120 + 147/504 = 267/504 - 267/504 simplified gives 89/168
- So, 20/84 + 21/72 = 89/168
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