Add 20/18 and 42/21
1st number: 1 2/18, 2nd number: 2 0/21
20/18 + 42/21 is 28/9.
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,
20/18 = 20 × 7/18 × 7 = 140/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Add the two like fractions:
140/126 + 252/126 = 140 + 252/126 = 392/126 - 392/126 simplified gives 28/9
- So, 20/18 + 42/21 = 28/9
In mixed form: 31/9
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