Answers

Subtract 56/90 from 42/21

1^st number: 2 0/21, 2^nd number: 56/90

42/21 - 56/90 is 62/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 21 × 30 = 630,
   42/21 = 42 × 30/21 × 30 = 1260/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   56/90 = 56 × 7/90 × 7 = 392/630
4. Subtract the two like fractions:
   1260/630 - 392/630 = 1260 - 392/630 = 868/630
5. After reducing the fraction, the answer is 62/45
6. In mixed form: 117/45

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