Subtract 70/80 from 7/42
7/42 - 70/80 is -17/24.
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,
7/42 = 7 × 40/42 × 40 = 280/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Subtract the two like fractions:
280/1680 - 1470/1680 = 280 - 1470/1680 = -1190/1680 - After reducing the fraction, the answer is -17/24
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