Answers

Subtract 70/20 from 42/72

1^st number: 42/72, 2^nd number: 3 10/20

42/72 - 70/20 is -35/12.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 20 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 72 × 5 = 360,
   42/72 = 42 × 5/72 × 5 = 210/360
3. Likewise, for the 2nd fraction, since 20 × 18 = 360,
   70/20 = 70 × 18/20 × 18 = 1260/360
4. Subtract the two like fractions:
   210/360 - 1260/360 = 210 - 1260/360 = -1050/360
5. After reducing the fraction, the answer is -35/12

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