Add 81/80 and 21/90
1st number: 1 1/80, 2nd number: 21/90
81/80 + 21/90 is 299/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Add the two like fractions:
729/720 + 168/720 = 729 + 168/720 = 897/720 - 897/720 simplified gives 299/240
- So, 81/80 + 21/90 = 299/240
In mixed form: 159/240
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