Answers

Subtract 21/40 from 70/80

70/80 - 21/40 is 7/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 40 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 80 × 1 = 80,
   70/80 = 70 × 1/80 × 1 = 70/80
3. Likewise, for the 2nd fraction, since 40 × 2 = 80,
   21/40 = 21 × 2/40 × 2 = 42/80
4. Subtract the two like fractions:
   70/80 - 42/80 = 70 - 42/80 = 28/80
5. After reducing the fraction, the answer is 7/20

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