Subtract 40/45 from 12/20
12/20 - 40/45 is -13/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
12/20 = 12 × 9/20 × 9 = 108/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
40/45 = 40 × 4/45 × 4 = 160/180 - Subtract the two like fractions:
108/180 - 160/180 = 108 - 160/180 = -52/180 - After reducing the fraction, the answer is -13/45
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