Subtract 30/50 from 20/45
20/45 - 30/50 is -7/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 45 × 10 = 450,
20/45 = 20 × 10/45 × 10 = 200/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
30/50 = 30 × 9/50 × 9 = 270/450 - Subtract the two like fractions:
200/450 - 270/450 = 200 - 270/450 = -70/450 - After reducing the fraction, the answer is -7/45
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