Subtract 4/42 from 7/80
7/80 - 4/42 is -13/1680.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
7/80 = 7 × 21/80 × 21 = 147/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
4/42 = 4 × 40/42 × 40 = 160/1680 - Subtract the two like fractions:
147/1680 - 160/1680 = 147 - 160/1680 = -13/1680
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