Add 20/21 and 30/18
1st number: 20/21, 2nd number: 1 12/18
20/21 + 30/18 is 55/21.
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,
30/18 = 30 × 7/18 × 7 = 210/126 - Add the two like fractions:
120/126 + 210/126 = 120 + 210/126 = 330/126 - 330/126 simplified gives 55/21
- So, 20/21 + 30/18 = 55/21
In mixed form: 213/21
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