Subtract 30/90 from 20/75
20/75 - 30/90 is -1/15.
Steps for subtracting fractions
- 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 - For the 1st fraction, since 75 × 6 = 450,
20/75 = 20 × 6/75 × 6 = 120/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
30/90 = 30 × 5/90 × 5 = 150/450 - Subtract the two like fractions:
120/450 - 150/450 = 120 - 150/450 = -30/450 - After reducing the fraction, the answer is -1/15
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