Answers

Subtract 45/80 from 21/60

21/60 - 45/80 is -17/80.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 80 is 240
   
   Next, find the equivalent fraction of both fractional numbers with denominator 240
2. For the 1st fraction, since 60 × 4 = 240,
   21/60 = 21 × 4/60 × 4 = 84/240
3. Likewise, for the 2nd fraction, since 80 × 3 = 240,
   45/80 = 45 × 3/80 × 3 = 135/240
4. Subtract the two like fractions:
   84/240 - 135/240 = 84 - 135/240 = -51/240
5. After reducing the fraction, the answer is -17/80

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