Add 20/21 and 18/28
20/21 + 18/28 is 67/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Add the two like fractions:
80/84 + 54/84 = 80 + 54/84 = 134/84 - 134/84 simplified gives 67/42
- So, 20/21 + 18/28 = 67/42
In mixed form: 125/42
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