Answers

Subtract 28/80 from 40/70

40/70 - 28/80 is 31/140.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 80 is 560
   
   Next, find the equivalent fraction of both fractional numbers with denominator 560
2. For the 1st fraction, since 70 × 8 = 560,
   40/70 = 40 × 8/70 × 8 = 320/560
3. Likewise, for the 2nd fraction, since 80 × 7 = 560,
   28/80 = 28 × 7/80 × 7 = 196/560
4. Subtract the two like fractions:
   320/560 - 196/560 = 320 - 196/560 = 124/560
5. After reducing the fraction, the answer is 31/140

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