Subtract 40/80 from 40/42
40/42 - 40/80 is 19/42.
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,
40/42 = 40 × 40/42 × 40 = 1600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
40/80 = 40 × 21/80 × 21 = 840/1680 - Subtract the two like fractions:
1600/1680 - 840/1680 = 1600 - 840/1680 = 760/1680 - After reducing the fraction, the answer is 19/42
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