Answers

Subtract 30/21 from 42/60

1^st number: 42/60, 2^nd number: 1 9/21

42/60 - 30/21 is -51/70.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 21 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 60 × 7 = 420,
   42/60 = 42 × 7/60 × 7 = 294/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   30/21 = 30 × 20/21 × 20 = 600/420
4. Subtract the two like fractions:
   294/420 - 600/420 = 294 - 600/420 = -306/420
5. After reducing the fraction, the answer is -51/70

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