Subtract 20/42 from 15/63
15/63 - 20/42 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 63 × 2 = 126,
15/63 = 15 × 2/63 × 2 = 30/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
20/42 = 20 × 3/42 × 3 = 60/126 - Subtract the two like fractions:
30/126 - 60/126 = 30 - 60/126 = -30/126 - After reducing the fraction, the answer is -5/21
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