Subtract 80/42 from 70/40
1st number: 1 30/40, 2nd number: 1 38/42
70/40 - 80/42 is -13/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
80/42 = 80 × 20/42 × 20 = 1600/840 - Subtract the two like fractions:
1470/840 - 1600/840 = 1470 - 1600/840 = -130/840 - After reducing the fraction, the answer is -13/84
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