Answers

Subtract 8/30 from 21/90

21/90 - 8/30 is -1/30.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 30 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 90 × 1 = 90,
   21/90 = 21 × 1/90 × 1 = 21/90
3. Likewise, for the 2nd fraction, since 30 × 3 = 90,
   8/30 = 8 × 3/30 × 3 = 24/90
4. Subtract the two like fractions:
   21/90 - 24/90 = 21 - 24/90 = -3/90
5. After reducing the fraction, the answer is -1/30

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