Answers

Subtract 21/70 from 4/21

4/21 - 21/70 is -23/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 70 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 21 × 10 = 210,
   4/21 = 4 × 10/21 × 10 = 40/210
3. Likewise, for the 2nd fraction, since 70 × 3 = 210,
   21/70 = 21 × 3/70 × 3 = 63/210
4. Subtract the two like fractions:
   40/210 - 63/210 = 40 - 63/210 = -23/210

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