Subtract 75/80 from 42/84
42/84 - 75/80 is -7/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
42/84 = 42 × 20/84 × 20 = 840/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
75/80 = 75 × 21/80 × 21 = 1575/1680 - Subtract the two like fractions:
840/1680 - 1575/1680 = 840 - 1575/1680 = -735/1680 - After reducing the fraction, the answer is -7/16
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