Subtract 20/90 from 7/45
7/45 - 20/90 is -1/15.
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,
7/45 = 7 × 2/45 × 2 = 14/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Subtract the two like fractions:
14/90 - 20/90 = 14 - 20/90 = -6/90 - After reducing the fraction, the answer is -1/15
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