Add 21/12 and 84/9
1st number: 1 9/12, 2nd number: 9 3/9
21/12 + 84/9 is 133/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
84/9 = 84 × 4/9 × 4 = 336/36 - Add the two like fractions:
63/36 + 336/36 = 63 + 336/36 = 399/36 - 399/36 simplified gives 133/12
- So, 21/12 + 84/9 = 133/12
In mixed form: 111/12
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