Add 15/7 and 21/81
1st number: 2 1/7, 2nd number: 21/81
15/7 + 21/81 is 454/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 7 × 81 = 567,
15/7 = 15 × 81/7 × 81 = 1215/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Add the two like fractions:
1215/567 + 147/567 = 1215 + 147/567 = 1362/567 - 1362/567 simplified gives 454/189
- So, 15/7 + 21/81 = 454/189
In mixed form: 276/189
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