Subtract 45/27 from 20/42
1st number: 20/42, 2nd number: 1 18/27
20/42 - 45/27 is -25/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
45/27 = 45 × 14/27 × 14 = 630/378 - Subtract the two like fractions:
180/378 - 630/378 = 180 - 630/378 = -450/378 - After reducing the fraction, the answer is -25/21
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