Subtract 42/90 from 18/80
18/80 - 42/90 is -29/120.
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,
18/80 = 18 × 9/80 × 9 = 162/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
42/90 = 42 × 8/90 × 8 = 336/720 - Subtract the two like fractions:
162/720 - 336/720 = 162 - 336/720 = -174/720 - After reducing the fraction, the answer is -29/120
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