Subtract 45/42 from 20/40
1st number: 20/40, 2nd number: 1 3/42
20/40 - 45/42 is -4/7.
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,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
45/42 = 45 × 20/42 × 20 = 900/840 - Subtract the two like fractions:
420/840 - 900/840 = 420 - 900/840 = -480/840 - After reducing the fraction, the answer is -4/7
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