Subtract 42/45 from 54/80
54/80 - 42/45 is -31/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
54/80 = 54 × 9/80 × 9 = 486/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
42/45 = 42 × 16/45 × 16 = 672/720 - Subtract the two like fractions:
486/720 - 672/720 = 486 - 672/720 = -186/720 - After reducing the fraction, the answer is -31/120
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