Subtract 25/50 from 21/90
21/90 - 25/50 is -4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 90 × 5 = 450,
21/90 = 21 × 5/90 × 5 = 105/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
25/50 = 25 × 9/50 × 9 = 225/450 - Subtract the two like fractions:
105/450 - 225/450 = 105 - 225/450 = -120/450 - After reducing the fraction, the answer is -4/15
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