Subtract 28/80 from 8/42
8/42 - 28/80 is -67/420.
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,
8/42 = 8 × 40/42 × 40 = 320/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
28/80 = 28 × 21/80 × 21 = 588/1680 - Subtract the two like fractions:
320/1680 - 588/1680 = 320 - 588/1680 = -268/1680 - After reducing the fraction, the answer is -67/420
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