Subtract 9/80 from 20/40
20/40 - 9/80 is 31/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
20/40 = 20 × 2/40 × 2 = 40/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
9/80 = 9 × 1/80 × 1 = 9/80 - Subtract the two like fractions:
40/80 - 9/80 = 40 - 9/80 = 31/80
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