Subtract 27/20 from 20/42
1st number: 20/42, 2nd number: 1 7/20
20/42 - 27/20 is -367/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
20/42 = 20 × 10/42 × 10 = 200/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420 - Subtract the two like fractions:
200/420 - 567/420 = 200 - 567/420 = -367/420
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