Answers

Subtract 42/9 from 84/21

1^st number: 4 0/21, 2^nd number: 4 6/9

84/21 - 42/9 is -2/3.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 9 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 21 × 3 = 63,
   84/21 = 84 × 3/21 × 3 = 252/63
3. Likewise, for the 2nd fraction, since 9 × 7 = 63,
   42/9 = 42 × 7/9 × 7 = 294/63
4. Subtract the two like fractions:
   252/63 - 294/63 = 252 - 294/63 = -42/63
5. After reducing the fraction, the answer is -2/3

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