Add 54/18 and 70/21
1st number: 3 0/18, 2nd number: 3 7/21
54/18 + 70/21 is 19/3.
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,
54/18 = 54 × 7/18 × 7 = 378/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126 - Add the two like fractions:
378/126 + 420/126 = 378 + 420/126 = 798/126 - 798/126 simplified gives 19/3
- So, 54/18 + 70/21 = 19/3
In mixed form: 61/3
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