Subtract 21/36 from 20/45
20/45 - 21/36 is -5/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
20/45 = 20 × 4/45 × 4 = 80/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Subtract the two like fractions:
80/180 - 105/180 = 80 - 105/180 = -25/180 - After reducing the fraction, the answer is -5/36
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