Subtract 42/90 from 20/30
20/30 - 42/90 is 1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
20/30 = 20 × 3/30 × 3 = 60/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Subtract the two like fractions:
60/90 - 42/90 = 60 - 42/90 = 18/90 - After reducing the fraction, the answer is 1/5
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