Subtract 20/15 from 45/42
1st number: 1 3/42, 2nd number: 1 5/15
45/42 - 20/15 is -11/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
45/42 = 45 × 5/42 × 5 = 225/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
20/15 = 20 × 14/15 × 14 = 280/210 - Subtract the two like fractions:
225/210 - 280/210 = 225 - 280/210 = -55/210 - After reducing the fraction, the answer is -11/42
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