Add 21/18 and 20/28
1st number: 1 3/18, 2nd number: 20/28
21/18 + 20/28 is 79/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 28 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 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252 - Add the two like fractions:
294/252 + 180/252 = 294 + 180/252 = 474/252 - 474/252 simplified gives 79/42
- So, 21/18 + 20/28 = 79/42
In mixed form: 137/42
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