Add 81/21 and 42/49
1st number: 3 18/21, 2nd number: 42/49
81/21 + 42/49 is 33/7.
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,
81/21 = 81 × 7/21 × 7 = 567/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
42/49 = 42 × 3/49 × 3 = 126/147 - Add the two like fractions:
567/147 + 126/147 = 567 + 126/147 = 693/147 - 693/147 simplified gives 33/7
- So, 81/21 + 42/49 = 33/7
In mixed form: 45/7
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