Subtract 8/20 from 1/45
1/45 - 8/20 is -17/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
1/45 = 1 × 4/45 × 4 = 4/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
8/20 = 8 × 9/20 × 9 = 72/180 - Subtract the two like fractions:
4/180 - 72/180 = 4 - 72/180 = -68/180 - After reducing the fraction, the answer is -17/45
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