Subtract 18/45 from 7/20
7/20 - 18/45 is -1/20.
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,
7/20 = 7 × 9/20 × 9 = 63/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
18/45 = 18 × 4/45 × 4 = 72/180 - Subtract the two like fractions:
63/180 - 72/180 = 63 - 72/180 = -9/180 - After reducing the fraction, the answer is -1/20
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