Answers

Subtract 42/70 from 28/80

28/80 - 42/70 is -1/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 70 is 560
   
   Next, find the equivalent fraction of both fractional numbers with denominator 560
2. For the 1st fraction, since 80 × 7 = 560,
   28/80 = 28 × 7/80 × 7 = 196/560
3. Likewise, for the 2nd fraction, since 70 × 8 = 560,
   42/70 = 42 × 8/70 × 8 = 336/560
4. Subtract the two like fractions:
   196/560 - 336/560 = 196 - 336/560 = -140/560
5. After reducing the fraction, the answer is -1/4

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