Add 30/21 and 54/18
1st number: 1 9/21, 2nd number: 3 0/18
30/21 + 54/18 is 31/7.
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,
30/21 = 30 × 6/21 × 6 = 180/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
54/18 = 54 × 7/18 × 7 = 378/126 - Add the two like fractions:
180/126 + 378/126 = 180 + 378/126 = 558/126 - 558/126 simplified gives 31/7
- So, 30/21 + 54/18 = 31/7
In mixed form: 43/7
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