Subtract 42/80 from 40/84
40/84 - 42/80 is -41/840.
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,
40/84 = 40 × 20/84 × 20 = 800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Subtract the two like fractions:
800/1680 - 882/1680 = 800 - 882/1680 = -82/1680 - After reducing the fraction, the answer is -41/840
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