Subtract 18/90 from 7/80
7/80 - 18/90 is -9/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
7/80 = 7 × 9/80 × 9 = 63/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
18/90 = 18 × 8/90 × 8 = 144/720 - Subtract the two like fractions:
63/720 - 144/720 = 63 - 144/720 = -81/720 - After reducing the fraction, the answer is -9/80
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