Subtract 49/80 from 16/42
16/42 - 49/80 is -389/1680.
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,
16/42 = 16 × 40/42 × 40 = 640/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
49/80 = 49 × 21/80 × 21 = 1029/1680 - Subtract the two like fractions:
640/1680 - 1029/1680 = 640 - 1029/1680 = -389/1680
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