Add 81/21 and 21/49
1st number: 3 18/21, 2nd number: 21/49
81/21 + 21/49 is 30/7.
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,
21/49 = 21 × 3/49 × 3 = 63/147 - Add the two like fractions:
567/147 + 63/147 = 567 + 63/147 = 630/147 - 630/147 simplified gives 30/7
- So, 81/21 + 21/49 = 30/7
In mixed form: 42/7
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