Add 21/18 and 42/84
1st number: 1 3/18, 2nd number: 42/84
21/18 + 42/84 is 5/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 84 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 18 × 14 = 252,
21/18 = 21 × 14/18 × 14 = 294/252 - Likewise, for the 2nd fraction, since 84 × 3 = 252,
42/84 = 42 × 3/84 × 3 = 126/252 - Add the two like fractions:
294/252 + 126/252 = 294 + 126/252 = 420/252 - 420/252 simplified gives 5/3
- So, 21/18 + 42/84 = 5/3
In mixed form: 12/3
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