Answers

Subtract 63/18 from 70/21

1^st number: 3 7/21, 2^nd number: 3 9/18

70/21 - 63/18 is -1/6.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 18 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 21 × 6 = 126,
   70/21 = 70 × 6/21 × 6 = 420/126
3. Likewise, for the 2nd fraction, since 18 × 7 = 126,
   63/18 = 63 × 7/18 × 7 = 441/126
4. Subtract the two like fractions:
   420/126 - 441/126 = 420 - 441/126 = -21/126
5. After reducing the fraction, the answer is -1/6

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