Subtract 21/50 from 7/18
7/18 - 21/50 is -7/225.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 18 × 25 = 450,
7/18 = 7 × 25/18 × 25 = 175/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
21/50 = 21 × 9/50 × 9 = 189/450 - Subtract the two like fractions:
175/450 - 189/450 = 175 - 189/450 = -14/450 - After reducing the fraction, the answer is -7/225
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