Subtract 9/84 from 20/42
20/42 - 9/84 is 31/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
9/84 = 9 × 1/84 × 1 = 9/84 - Subtract the two like fractions:
40/84 - 9/84 = 40 - 9/84 = 31/84
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