Answers

Subtract 42/20 from 90/70

1^st number: 1 20/70, 2^nd number: 2 2/20

90/70 - 42/20 is -57/70.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 20 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 70 × 2 = 140,
   90/70 = 90 × 2/70 × 2 = 180/140
3. Likewise, for the 2nd fraction, since 20 × 7 = 140,
   42/20 = 42 × 7/20 × 7 = 294/140
4. Subtract the two like fractions:
   180/140 - 294/140 = 180 - 294/140 = -114/140
5. After reducing the fraction, the answer is -57/70

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