Answers

Subtract 40/21 from 90/84

1^st number: 1 6/84, 2^nd number: 1 19/21

90/84 - 40/21 is -5/6.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 84 × 1 = 84,
   90/84 = 90 × 1/84 × 1 = 90/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   40/21 = 40 × 4/21 × 4 = 160/84
4. Subtract the two like fractions:
   90/84 - 160/84 = 90 - 160/84 = -70/84
5. After reducing the fraction, the answer is -5/6

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