Add 90/21 and 80/81
1st number: 4 6/21, 2nd number: 80/81
90/21 + 80/81 is 2990/567.
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,
90/21 = 90 × 27/21 × 27 = 2430/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
80/81 = 80 × 7/81 × 7 = 560/567 - Add the two like fractions:
2430/567 + 560/567 = 2430 + 560/567 = 2990/567 - So, 90/21 + 80/81 = 2990/567
In mixed form: 5155/567
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