Add 12/21 and 42/49
12/21 + 42/49 is 10/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
12/21 = 12 × 7/21 × 7 = 84/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
42/49 = 42 × 3/49 × 3 = 126/147 - Add the two like fractions:
84/147 + 126/147 = 84 + 126/147 = 210/147 - 210/147 simplified gives 10/7
- So, 12/21 + 42/49 = 10/7
In mixed form: 13/7
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