Add 12/21 and 20/36
12/21 + 20/36 is 71/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
12/21 = 12 × 12/21 × 12 = 144/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Add the two like fractions:
144/252 + 140/252 = 144 + 140/252 = 284/252 - 284/252 simplified gives 71/63
- So, 12/21 + 20/36 = 71/63
In mixed form: 18/63
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