Add 20/21 and 3/18
20/21 + 3/18 is 47/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
3/18 = 3 × 7/18 × 7 = 21/126 - Add the two like fractions:
120/126 + 21/126 = 120 + 21/126 = 141/126 - 141/126 simplified gives 47/42
- So, 20/21 + 3/18 = 47/42
In mixed form: 15/42
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