Subtract 20/42 from 15/18
15/18 - 20/42 is 5/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
20/42 = 20 × 3/42 × 3 = 60/126 - Subtract the two like fractions:
105/126 - 60/126 = 105 - 60/126 = 45/126 - After reducing the fraction, the answer is 5/14
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