Add 70/42 and 90/81
1st number: 1 28/42, 2nd number: 1 9/81
70/42 + 90/81 is 25/9.
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,
70/42 = 70 × 27/42 × 27 = 1890/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
90/81 = 90 × 14/81 × 14 = 1260/1134 - Add the two like fractions:
1890/1134 + 1260/1134 = 1890 + 1260/1134 = 3150/1134 - 3150/1134 simplified gives 25/9
- So, 70/42 + 90/81 = 25/9
In mixed form: 27/9
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