Subtract 15/42 from 5/20
5/20 - 15/42 is -3/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
15/42 = 15 × 10/42 × 10 = 150/420 - Subtract the two like fractions:
105/420 - 150/420 = 105 - 150/420 = -45/420 - After reducing the fraction, the answer is -3/28
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