Subtract 42/90 from 21/50
21/50 - 42/90 is -7/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 50 × 9 = 450,
21/50 = 21 × 9/50 × 9 = 189/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
42/90 = 42 × 5/90 × 5 = 210/450 - Subtract the two like fractions:
189/450 - 210/450 = 189 - 210/450 = -21/450 - After reducing the fraction, the answer is -7/150
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