Add 21/84 and 15/36
21/84 + 15/36 is 2/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
15/36 = 15 × 7/36 × 7 = 105/252 - Add the two like fractions:
63/252 + 105/252 = 63 + 105/252 = 168/252 - 168/252 simplified gives 2/3
- So, 21/84 + 15/36 = 2/3
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