Add 9/18 and 12/21
9/18 + 12/21 is 15/14.
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,
9/18 = 9 × 7/18 × 7 = 63/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
12/21 = 12 × 6/21 × 6 = 72/126 - Add the two like fractions:
63/126 + 72/126 = 63 + 72/126 = 135/126 - 135/126 simplified gives 15/14
- So, 9/18 + 12/21 = 15/14
In mixed form: 11/14
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