Answers

Subtract 70/80 from 80/42

1^st number: 1 38/42, 2^nd number: 70/80

80/42 - 70/80 is 173/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 42 × 40 = 1680,
   80/42 = 80 × 40/42 × 40 = 3200/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   70/80 = 70 × 21/80 × 21 = 1470/1680
4. Subtract the two like fractions:
   3200/1680 - 1470/1680 = 3200 - 1470/1680 = 1730/1680
5. After reducing the fraction, the answer is 173/168
6. In mixed form: 15/168

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