Answers

Subtract 21/28 from 90/30

1^st number: 3 0/30, 2^nd number: 21/28

90/30 - 21/28 is 9/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 28 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 30 × 14 = 420,
   90/30 = 90 × 14/30 × 14 = 1260/420
3. Likewise, for the 2nd fraction, since 28 × 15 = 420,
   21/28 = 21 × 15/28 × 15 = 315/420
4. Subtract the two like fractions:
   1260/420 - 315/420 = 1260 - 315/420 = 945/420
5. After reducing the fraction, the answer is 9/4
6. In mixed form: 21/4

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