Subtract 1/20 from 42/90
42/90 - 1/20 is 5/12.
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,
1/20 = 1 × 9/20 × 9 = 9/180 - Subtract the two like fractions:
84/180 - 9/180 = 84 - 9/180 = 75/180 - After reducing the fraction, the answer is 5/12
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