Subtract 42/90 from 15/20
15/20 - 42/90 is 17/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
15/20 = 15 × 9/20 × 9 = 135/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
42/90 = 42 × 2/90 × 2 = 84/180 - Subtract the two like fractions:
135/180 - 84/180 = 135 - 84/180 = 51/180 - After reducing the fraction, the answer is 17/60
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