Subtract 42/20 from 21/90
1st number: 21/90, 2nd number: 2 2/20
21/90 - 42/20 is -28/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Subtract the two like fractions:
42/180 - 378/180 = 42 - 378/180 = -336/180 - After reducing the fraction, the answer is -28/15
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