Answers

Subtract 10/90 from 21/40

21/40 - 10/90 is 149/360.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 90 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 90 × 4 = 360,
   10/90 = 10 × 4/90 × 4 = 40/360
4. Subtract the two like fractions:
   189/360 - 40/360 = 189 - 40/360 = 149/360

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