Answers

Subtract 9/4 from 21/30

1^st number: 21/30, 2^nd number: 2 1/4

21/30 - 9/4 is -31/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 4 is 60
   
   Next, find the equivalent fraction of both fractional numbers with denominator 60
2. For the 1st fraction, since 30 × 2 = 60,
   21/30 = 21 × 2/30 × 2 = 42/60
3. Likewise, for the 2nd fraction, since 4 × 15 = 60,
   9/4 = 9 × 15/4 × 15 = 135/60
4. Subtract the two like fractions:
   42/60 - 135/60 = 42 - 135/60 = -93/60
5. After reducing the fraction, the answer is -31/20

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