Subtract 12/20 from 42/90
42/90 - 12/20 is -2/15.
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,
42/90 = 42 × 2/90 × 2 = 84/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
12/20 = 12 × 9/20 × 9 = 108/180 - Subtract the two like fractions:
84/180 - 108/180 = 84 - 108/180 = -24/180 - After reducing the fraction, the answer is -2/15
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