Subtract 5/20 from 7/42
7/42 - 5/20 is -1/12.
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,
7/42 = 7 × 10/42 × 10 = 70/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420 - Subtract the two like fractions:
70/420 - 105/420 = 70 - 105/420 = -35/420 - After reducing the fraction, the answer is -1/12
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