Subtract 40/21 from 90/80
1st number: 1 10/80, 2nd number: 1 19/21
90/80 - 40/21 is -131/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
40/21 = 40 × 80/21 × 80 = 3200/1680 - Subtract the two like fractions:
1890/1680 - 3200/1680 = 1890 - 3200/1680 = -1310/1680 - After reducing the fraction, the answer is -131/168
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