Subtract 20/35 from 18/42
18/42 - 20/35 is -1/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
20/35 = 20 × 6/35 × 6 = 120/210 - Subtract the two like fractions:
90/210 - 120/210 = 90 - 120/210 = -30/210 - After reducing the fraction, the answer is -1/7
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