Add 80/21 and 90/81
1st number: 3 17/21, 2nd number: 1 9/81
80/21 + 90/81 is 310/63.
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,
80/21 = 80 × 27/21 × 27 = 2160/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Add the two like fractions:
2160/567 + 630/567 = 2160 + 630/567 = 2790/567 - 2790/567 simplified gives 310/63
- So, 80/21 + 90/81 = 310/63
In mixed form: 458/63
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