Answers

Subtract 18/80 from 70/42

1^st number: 1 28/42, 2^nd number: 18/80

70/42 - 18/80 is 173/120.

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,
   70/42 = 70 × 40/42 × 40 = 2800/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   18/80 = 18 × 21/80 × 21 = 378/1680
4. Subtract the two like fractions:
   2800/1680 - 378/1680 = 2800 - 378/1680 = 2422/1680
5. After reducing the fraction, the answer is 173/120
6. In mixed form: 153/120

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