Add 81/28 and 21/20
1st number: 2 25/28, 2nd number: 1 1/20
81/28 + 21/20 is 138/35.
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,
81/28 = 81 × 5/28 × 5 = 405/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Add the two like fractions:
405/140 + 147/140 = 405 + 147/140 = 552/140 - 552/140 simplified gives 138/35
- So, 81/28 + 21/20 = 138/35
In mixed form: 333/35
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