Subtract 49/80 from 1/42
1/42 - 49/80 is -989/1680.
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,
1/42 = 1 × 40/42 × 40 = 40/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
49/80 = 49 × 21/80 × 21 = 1029/1680 - Subtract the two like fractions:
40/1680 - 1029/1680 = 40 - 1029/1680 = -989/1680
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