Answers

Subtract 16/45 from 21/72

21/72 - 16/45 is -23/360.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 45 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 72 × 5 = 360,
   21/72 = 21 × 5/72 × 5 = 105/360
3. Likewise, for the 2nd fraction, since 45 × 8 = 360,
   16/45 = 16 × 8/45 × 8 = 128/360
4. Subtract the two like fractions:
   105/360 - 128/360 = 105 - 128/360 = -23/360

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