Answers

Subtract 21/20 from 7/40

1^st number: 7/40, 2^nd number: 1 1/20

7/40 - 21/20 is -7/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 20 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 40 × 1 = 40,
   7/40 = 7 × 1/40 × 1 = 7/40
3. Likewise, for the 2nd fraction, since 20 × 2 = 40,
   21/20 = 21 × 2/20 × 2 = 42/40
4. Subtract the two like fractions:
   7/40 - 42/40 = 7 - 42/40 = -35/40
5. After reducing the fraction, the answer is -7/8

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