Subtract 90/80 from 5/42
1st number: 5/42, 2nd number: 1 10/80
5/42 - 90/80 is -169/168.
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,
5/42 = 5 × 40/42 × 40 = 200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680 - Subtract the two like fractions:
200/1680 - 1890/1680 = 200 - 1890/1680 = -1690/1680 - After reducing the fraction, the answer is -169/168
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