Add 15/36 and 20/21
15/36 + 20/21 is 115/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
15/36 = 15 × 7/36 × 7 = 105/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
20/21 = 20 × 12/21 × 12 = 240/252 - Add the two like fractions:
105/252 + 240/252 = 105 + 240/252 = 345/252 - 345/252 simplified gives 115/84
- So, 15/36 + 20/21 = 115/84
In mixed form: 131/84
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