Add 7/18 and 20/21
7/18 + 20/21 is 169/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
7/18 = 7 × 7/18 × 7 = 49/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Add the two like fractions:
49/126 + 120/126 = 49 + 120/126 = 169/126 - So, 7/18 + 20/21 = 169/126
In mixed form: 143/126
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