Add 28/20 and 81/90
1st number: 1 8/20, 2nd number: 81/90
28/20 + 81/90 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
252/180 + 162/180 = 252 + 162/180 = 414/180 - 414/180 simplified gives 23/10
- So, 28/20 + 81/90 = 23/10
In mixed form: 23/10
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