Subtract 18/36 from 21/50
21/50 - 18/36 is -2/25.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 36 is 900
Next, find the equivalent fraction of both fractional numbers with denominator 900 - For the 1st fraction, since 50 × 18 = 900,
21/50 = 21 × 18/50 × 18 = 378/900 - Likewise, for the 2nd fraction, since 36 × 25 = 900,
18/36 = 18 × 25/36 × 25 = 450/900 - Subtract the two like fractions:
378/900 - 450/900 = 378 - 450/900 = -72/900 - After reducing the fraction, the answer is -2/25
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