Answers

Subtract 70/90 from 20/75

20/75 - 70/90 is -23/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 75 and 90 is 450
   
   Next, find the equivalent fraction of both fractional numbers with denominator 450
2. For the 1st fraction, since 75 × 6 = 450,
   20/75 = 20 × 6/75 × 6 = 120/450
3. Likewise, for the 2nd fraction, since 90 × 5 = 450,
   70/90 = 70 × 5/90 × 5 = 350/450
4. Subtract the two like fractions:
   120/450 - 350/450 = 120 - 350/450 = -230/450
5. After reducing the fraction, the answer is -23/45

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