Add 21/42 and 90/81
1st number: 21/42, 2nd number: 1 9/81
21/42 + 90/81 is 29/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
21/42 = 21 × 27/42 × 27 = 567/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
90/81 = 90 × 14/81 × 14 = 1260/1134 - Add the two like fractions:
567/1134 + 1260/1134 = 567 + 1260/1134 = 1827/1134 - 1827/1134 simplified gives 29/18
- So, 21/42 + 90/81 = 29/18
In mixed form: 111/18
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