Subtract 40/21 from 20/80
1st number: 20/80, 2nd number: 1 19/21
20/80 - 40/21 is -139/84.
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,
20/80 = 20 × 21/80 × 21 = 420/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
40/21 = 40 × 80/21 × 80 = 3200/1680 - Subtract the two like fractions:
420/1680 - 3200/1680 = 420 - 3200/1680 = -2780/1680 - After reducing the fraction, the answer is -139/84
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