Answers

Subtract 16/30 from 21/90

21/90 - 16/30 is -3/10.

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,
   16/30 = 16 × 3/30 × 3 = 48/90
4. Subtract the two like fractions:
   21/90 - 48/90 = 21 - 48/90 = -27/90
5. After reducing the fraction, the answer is -3/10

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