Subtract 30/20 from 27/42
1st number: 27/42, 2nd number: 1 10/20
27/42 - 30/20 is -6/7.
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,
27/42 = 27 × 10/42 × 10 = 270/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420 - Subtract the two like fractions:
270/420 - 630/420 = 270 - 630/420 = -360/420 - After reducing the fraction, the answer is -6/7
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