Subtract 45/80 from 42/90
42/90 - 45/80 is -23/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
42/90 = 42 × 8/90 × 8 = 336/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
45/80 = 45 × 9/80 × 9 = 405/720 - Subtract the two like fractions:
336/720 - 405/720 = 336 - 405/720 = -69/720 - After reducing the fraction, the answer is -23/240
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