Add 20/21 and 56/72
20/21 + 56/72 is 109/63.
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,
56/72 = 56 × 7/72 × 7 = 392/504 - Add the two like fractions:
480/504 + 392/504 = 480 + 392/504 = 872/504 - 872/504 simplified gives 109/63
- So, 20/21 + 56/72 = 109/63
In mixed form: 146/63
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