Add 12/72 and 20/21
12/72 + 20/21 is 47/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
20/21 = 20 × 24/21 × 24 = 480/504 - Add the two like fractions:
84/504 + 480/504 = 84 + 480/504 = 564/504 - 564/504 simplified gives 47/42
- So, 12/72 + 20/21 = 47/42
In mixed form: 15/42
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