Add 1/21 and 30/18
1st number: 1/21, 2nd number: 1 12/18
1/21 + 30/18 is 12/7.
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,
1/21 = 1 × 6/21 × 6 = 6/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126 - Add the two like fractions:
6/126 + 210/126 = 6 + 210/126 = 216/126 - 216/126 simplified gives 12/7
- So, 1/21 + 30/18 = 12/7
In mixed form: 15/7
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