Add 21/42 and 12/9
1st number: 21/42, 2nd number: 1 3/9
21/42 + 12/9 is 11/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126 - Add the two like fractions:
63/126 + 168/126 = 63 + 168/126 = 231/126 - 231/126 simplified gives 11/6
- So, 21/42 + 12/9 = 11/6
In mixed form: 15/6
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