Answers

Subtract 21/80 from 28/45

28/45 - 21/80 is 259/720.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 45 × 16 = 720,
   28/45 = 28 × 16/45 × 16 = 448/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   21/80 = 21 × 9/80 × 9 = 189/720
4. Subtract the two like fractions:
   448/720 - 189/720 = 448 - 189/720 = 259/720

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