Answers

Subtract 40/21 from 42/70

1^st number: 42/70, 2^nd number: 1 19/21

42/70 - 40/21 is -137/105.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 21 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 70 × 3 = 210,
   42/70 = 42 × 3/70 × 3 = 126/210
3. Likewise, for the 2nd fraction, since 21 × 10 = 210,
   40/21 = 40 × 10/21 × 10 = 400/210
4. Subtract the two like fractions:
   126/210 - 400/210 = 126 - 400/210 = -274/210
5. After reducing the fraction, the answer is -137/105

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