Add 28/80 and 21/90
28/80 + 21/90 is 7/12.
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,
21/90 = 21 × 8/90 × 8 = 168/720 - Add the two like fractions:
252/720 + 168/720 = 252 + 168/720 = 420/720 - 420/720 simplified gives 7/12
- So, 28/80 + 21/90 = 7/12
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