Add 28/80 and 81/90
28/80 + 81/90 is 5/4.
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,
28/80 = 28 × 9/80 × 9 = 252/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
81/90 = 81 × 8/90 × 8 = 648/720 - Add the two like fractions:
252/720 + 648/720 = 252 + 648/720 = 900/720 - 900/720 simplified gives 5/4
- So, 28/80 + 81/90 = 5/4
In mixed form: 11/4
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