Answers

Subtract 24/40 from 21/90

21/90 - 24/40 is -11/30.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 40 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 90 × 4 = 360,
   21/90 = 21 × 4/90 × 4 = 84/360
3. Likewise, for the 2nd fraction, since 40 × 9 = 360,
   24/40 = 24 × 9/40 × 9 = 216/360
4. Subtract the two like fractions:
   84/360 - 216/360 = 84 - 216/360 = -132/360
5. After reducing the fraction, the answer is -11/30

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