Subtract 80/40 from 20/42
1st number: 20/42, 2nd number: 2 0/40
20/42 - 80/40 is -32/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
20/42 = 20 × 20/42 × 20 = 400/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
80/40 = 80 × 21/40 × 21 = 1680/840 - Subtract the two like fractions:
400/840 - 1680/840 = 400 - 1680/840 = -1280/840 - After reducing the fraction, the answer is -32/21
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