Add 21/36 and 18/21
21/36 + 18/21 is 121/84.
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,
21/36 = 21 × 7/36 × 7 = 147/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
18/21 = 18 × 12/21 × 12 = 216/252 - Add the two like fractions:
147/252 + 216/252 = 147 + 216/252 = 363/252 - 363/252 simplified gives 121/84
- So, 21/36 + 18/21 = 121/84
In mixed form: 137/84
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