Subtract 80/40 from 10/21
1st number: 10/21, 2nd number: 2 0/40
10/21 - 80/40 is -32/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
10/21 = 10 × 40/21 × 40 = 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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