Subtract 20/80 from 15/42
15/42 - 20/80 is 3/28.
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,
15/42 = 15 × 40/42 × 40 = 600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680 - Subtract the two like fractions:
600/1680 - 420/1680 = 600 - 420/1680 = 180/1680 - After reducing the fraction, the answer is 3/28
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