Answers

Subtract 42/40 from 30/70

1^st number: 30/70, 2^nd number: 1 2/40

30/70 - 42/40 is -87/140.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 40 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 70 × 4 = 280,
   30/70 = 30 × 4/70 × 4 = 120/280
3. Likewise, for the 2nd fraction, since 40 × 7 = 280,
   42/40 = 42 × 7/40 × 7 = 294/280
4. Subtract the two like fractions:
   120/280 - 294/280 = 120 - 294/280 = -174/280
5. After reducing the fraction, the answer is -87/140

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