Add 42/21 and 18/81
1st number: 2 0/21, 2nd number: 18/81
42/21 + 18/81 is 20/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
42/21 = 42 × 27/21 × 27 = 1134/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
18/81 = 18 × 7/81 × 7 = 126/567 - Add the two like fractions:
1134/567 + 126/567 = 1134 + 126/567 = 1260/567 - 1260/567 simplified gives 20/9
- So, 42/21 + 18/81 = 20/9
In mixed form: 22/9
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