Add 30/18 and 72/21
1st number: 1 12/18, 2nd number: 3 9/21
30/18 + 72/21 is 107/21.
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,
30/18 = 30 × 7/18 × 7 = 210/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
72/21 = 72 × 6/21 × 6 = 432/126 - Add the two like fractions:
210/126 + 432/126 = 210 + 432/126 = 642/126 - 642/126 simplified gives 107/21
- So, 30/18 + 72/21 = 107/21
In mixed form: 52/21
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