Subtract 40/42 from 40/63
40/63 - 40/42 is -20/63.
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,
40/63 = 40 × 2/63 × 2 = 80/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
40/42 = 40 × 3/42 × 3 = 120/126 - Subtract the two like fractions:
80/126 - 120/126 = 80 - 120/126 = -40/126 - After reducing the fraction, the answer is -20/63
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