Answers

Subtract 42/40 from 70/21

1^st number: 3 7/21, 2^nd number: 1 2/40

70/21 - 42/40 is 137/60.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 21 × 40 = 840,
   70/21 = 70 × 40/21 × 40 = 2800/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   42/40 = 42 × 21/40 × 21 = 882/840
4. Subtract the two like fractions:
   2800/840 - 882/840 = 2800 - 882/840 = 1918/840
5. After reducing the fraction, the answer is 137/60
6. In mixed form: 217/60

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