Subtract 25/50 from 42/90
42/90 - 25/50 is -1/30.
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,
42/90 = 42 × 5/90 × 5 = 210/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
25/50 = 25 × 9/50 × 9 = 225/450 - Subtract the two like fractions:
210/450 - 225/450 = 210 - 225/450 = -15/450 - After reducing the fraction, the answer is -1/30
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