Add 12/18 and 9/21
12/18 + 9/21 is 23/21.
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,
12/18 = 12 × 7/18 × 7 = 84/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
9/21 = 9 × 6/21 × 6 = 54/126 - Add the two like fractions:
84/126 + 54/126 = 84 + 54/126 = 138/126 - 138/126 simplified gives 23/21
- So, 12/18 + 9/21 = 23/21
In mixed form: 12/21
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