Subtract 70/40 from 20/42
1st number: 20/42, 2nd number: 1 30/40
20/42 - 70/40 is -107/84.
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,
70/40 = 70 × 21/40 × 21 = 1470/840 - Subtract the two like fractions:
400/840 - 1470/840 = 400 - 1470/840 = -1070/840 - After reducing the fraction, the answer is -107/84
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