Subtract 18/42 from 5/15
5/15 - 18/42 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
5/15 = 5 × 14/15 × 14 = 70/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210 - Subtract the two like fractions:
70/210 - 90/210 = 70 - 90/210 = -20/210 - After reducing the fraction, the answer is -2/21
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