Add 21/81 and 42/49
21/81 + 42/49 is 211/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 49 is 3969
Next, find the equivalent fraction of both fractional numbers with denominator 3969 - For the 1st fraction, since 81 × 49 = 3969,
21/81 = 21 × 49/81 × 49 = 1029/3969 - Likewise, for the 2nd fraction, since 49 × 81 = 3969,
42/49 = 42 × 81/49 × 81 = 3402/3969 - Add the two like fractions:
1029/3969 + 3402/3969 = 1029 + 3402/3969 = 4431/3969 - 4431/3969 simplified gives 211/189
- So, 21/81 + 42/49 = 211/189
In mixed form: 122/189
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