Subtract 21/45 from 5/18
5/18 - 21/45 is -17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
5/18 = 5 × 5/18 × 5 = 25/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Subtract the two like fractions:
25/90 - 42/90 = 25 - 42/90 = -17/90
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