Add 90/28 and 81/20
1st number: 3 6/28, 2nd number: 4 1/20
90/28 + 81/20 is 1017/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
90/28 = 90 × 5/28 × 5 = 450/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Add the two like fractions:
450/140 + 567/140 = 450 + 567/140 = 1017/140 - So, 90/28 + 81/20 = 1017/140
In mixed form: 737/140
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