Add 18/21 and 42/49
18/21 + 42/49 is 12/7.
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,
18/21 = 18 × 7/21 × 7 = 126/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
42/49 = 42 × 3/49 × 3 = 126/147 - Add the two like fractions:
126/147 + 126/147 = 126 + 126/147 = 252/147 - 252/147 simplified gives 12/7
- So, 18/21 + 42/49 = 12/7
In mixed form: 15/7
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