Answers

Subtract 21/84 from 90/50

1^st number: 1 40/50, 2^nd number: 21/84

90/50 - 21/84 is 31/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 50 and 84 is 2100
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2100
2. For the 1st fraction, since 50 × 42 = 2100,
   90/50 = 90 × 42/50 × 42 = 3780/2100
3. Likewise, for the 2nd fraction, since 84 × 25 = 2100,
   21/84 = 21 × 25/84 × 25 = 525/2100
4. Subtract the two like fractions:
   3780/2100 - 525/2100 = 3780 - 525/2100 = 3255/2100
5. After reducing the fraction, the answer is 31/20
6. In mixed form: 111/20

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