Subtract 40/50 from 42/80
42/80 - 40/50 is -11/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 50 is 400
Next, find the equivalent fraction of both fractional numbers with denominator 400 - For the 1st fraction, since 80 × 5 = 400,
42/80 = 42 × 5/80 × 5 = 210/400 - Likewise, for the 2nd fraction, since 50 × 8 = 400,
40/50 = 40 × 8/50 × 8 = 320/400 - Subtract the two like fractions:
210/400 - 320/400 = 210 - 320/400 = -110/400 - After reducing the fraction, the answer is -11/40
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