Add 81/20 and 90/70
1st number: 4 1/20, 2nd number: 1 20/70
81/20 + 90/70 is 747/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
90/70 = 90 × 2/70 × 2 = 180/140 - Add the two like fractions:
567/140 + 180/140 = 567 + 180/140 = 747/140 - So, 81/20 + 90/70 = 747/140
In mixed form: 547/140
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