Subtract 18/15 from 3/42
1st number: 3/42, 2nd number: 1 3/15
3/42 - 18/15 is -79/70.
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,
3/42 = 3 × 5/42 × 5 = 15/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
18/15 = 18 × 14/15 × 14 = 252/210 - Subtract the two like fractions:
15/210 - 252/210 = 15 - 252/210 = -237/210 - After reducing the fraction, the answer is -79/70
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