Add 9/12 and 18/21
9/12 + 18/21 is 45/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
9/12 = 9 × 7/12 × 7 = 63/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Add the two like fractions:
63/84 + 72/84 = 63 + 72/84 = 135/84 - 135/84 simplified gives 45/28
- So, 9/12 + 18/21 = 45/28
In mixed form: 117/28
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