Subtract 21/15 from 1/42
1st number: 1/42, 2nd number: 1 6/15
1/42 - 21/15 is -289/210.
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,
1/42 = 1 × 5/42 × 5 = 5/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Subtract the two like fractions:
5/210 - 294/210 = 5 - 294/210 = -289/210
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