Subtract 1/45 from 18/20
18/20 - 1/45 is 79/90.
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,
18/20 = 18 × 9/20 × 9 = 162/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
1/45 = 1 × 4/45 × 4 = 4/180 - Subtract the two like fractions:
162/180 - 4/180 = 162 - 4/180 = 158/180 - After reducing the fraction, the answer is 79/90
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