Subtract 42/90 from 21/25
21/25 - 42/90 is 28/75.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 25 × 18 = 450,
21/25 = 21 × 18/25 × 18 = 378/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
42/90 = 42 × 5/90 × 5 = 210/450 - Subtract the two like fractions:
378/450 - 210/450 = 378 - 210/450 = 168/450 - After reducing the fraction, the answer is 28/75
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