Answers

Subtract 20/21 from 70/40

1^st number: 1 30/40, 2^nd number: 20/21

70/40 - 20/21 is 67/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 21 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   70/40 = 70 × 21/40 × 21 = 1470/840
3. Likewise, for the 2nd fraction, since 21 × 40 = 840,
   20/21 = 20 × 40/21 × 40 = 800/840
4. Subtract the two like fractions:
   1470/840 - 800/840 = 1470 - 800/840 = 670/840
5. After reducing the fraction, the answer is 67/84

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