Answers

Subtract 40/70 from 21/50

21/50 - 40/70 is -53/350.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 50 and 70 is 350
   
   Next, find the equivalent fraction of both fractional numbers with denominator 350
2. For the 1st fraction, since 50 × 7 = 350,
   21/50 = 21 × 7/50 × 7 = 147/350
3. Likewise, for the 2nd fraction, since 70 × 5 = 350,
   40/70 = 40 × 5/70 × 5 = 200/350
4. Subtract the two like fractions:
   147/350 - 200/350 = 147 - 200/350 = -53/350

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