Subtract 42/90 from 20/36
20/36 - 42/90 is 4/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
20/36 = 20 × 5/36 × 5 = 100/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
42/90 = 42 × 2/90 × 2 = 84/180 - Subtract the two like fractions:
100/180 - 84/180 = 100 - 84/180 = 16/180 - After reducing the fraction, the answer is 4/45
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