Subtract 75/80 from 20/42
20/42 - 75/80 is -155/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
20/42 = 20 × 40/42 × 40 = 800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
75/80 = 75 × 21/80 × 21 = 1575/1680 - Subtract the two like fractions:
800/1680 - 1575/1680 = 800 - 1575/1680 = -775/1680 - After reducing the fraction, the answer is -155/336
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