Subtract 45/20 from 20/42
1st number: 20/42, 2nd number: 2 5/20
20/42 - 45/20 is -149/84.
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,
45/20 = 45 × 21/20 × 21 = 945/420 - Subtract the two like fractions:
200/420 - 945/420 = 200 - 945/420 = -745/420 - After reducing the fraction, the answer is -149/84
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