Add 21/36 and 42/84
21/36 + 42/84 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 84 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 84 × 3 = 252,
42/84 = 42 × 3/84 × 3 = 126/252 - Add the two like fractions:
147/252 + 126/252 = 147 + 126/252 = 273/252 - 273/252 simplified gives 13/12
- So, 21/36 + 42/84 = 13/12
In mixed form: 11/12
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