Add 20/21 and 28/72
20/21 + 28/72 is 169/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
20/21 = 20 × 24/21 × 24 = 480/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
28/72 = 28 × 7/72 × 7 = 196/504 - Add the two like fractions:
480/504 + 196/504 = 480 + 196/504 = 676/504 - 676/504 simplified gives 169/126
- So, 20/21 + 28/72 = 169/126
In mixed form: 143/126
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