Answers

Subtract 70/15 from 21/40

1^st number: 21/40, 2^nd number: 4 10/15

21/40 - 70/15 is -497/120.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 15 is 120
   
   Next, find the equivalent fraction of both fractional numbers with denominator 120
2. For the 1st fraction, since 40 × 3 = 120,
   21/40 = 21 × 3/40 × 3 = 63/120
3. Likewise, for the 2nd fraction, since 15 × 8 = 120,
   70/15 = 70 × 8/15 × 8 = 560/120
4. Subtract the two like fractions:
   63/120 - 560/120 = 63 - 560/120 = -497/120

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