Subtract 21/90 from 8/45
8/45 - 21/90 is -1/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
8/45 = 8 × 2/45 × 2 = 16/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
16/90 - 21/90 = 16 - 21/90 = -5/90 - After reducing the fraction, the answer is -1/18
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