Add 70/21 and 42/81
1st number: 3 7/21, 2nd number: 42/81
70/21 + 42/81 is 104/27.
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,
70/21 = 70 × 27/21 × 27 = 1890/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Add the two like fractions:
1890/567 + 294/567 = 1890 + 294/567 = 2184/567 - 2184/567 simplified gives 104/27
- So, 70/21 + 42/81 = 104/27
In mixed form: 323/27
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