Answers

Subtract 16/45 from 21/40

21/40 - 16/45 is 61/360.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 45 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 40 × 9 = 360,
   21/40 = 21 × 9/40 × 9 = 189/360
3. Likewise, for the 2nd fraction, since 45 × 8 = 360,
   16/45 = 16 × 8/45 × 8 = 128/360
4. Subtract the two like fractions:
   189/360 - 128/360 = 189 - 128/360 = 61/360

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