Answers

Subtract 45/70 from 21/36

21/36 - 45/70 is -5/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 36 and 70 is 1260
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1260
2. For the 1st fraction, since 36 × 35 = 1260,
   21/36 = 21 × 35/36 × 35 = 735/1260
3. Likewise, for the 2nd fraction, since 70 × 18 = 1260,
   45/70 = 45 × 18/70 × 18 = 810/1260
4. Subtract the two like fractions:
   735/1260 - 810/1260 = 735 - 810/1260 = -75/1260
5. After reducing the fraction, the answer is -5/84

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