Subtract 7/15 from 18/42
18/42 - 7/15 is -4/105.
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,
18/42 = 18 × 5/42 × 5 = 90/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
7/15 = 7 × 14/15 × 14 = 98/210 - Subtract the two like fractions:
90/210 - 98/210 = 90 - 98/210 = -8/210 - After reducing the fraction, the answer is -4/105
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