Subtract 15/70 from 7/42
7/42 - 15/70 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
7/42 = 7 × 5/42 × 5 = 35/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
15/70 = 15 × 3/70 × 3 = 45/210 - Subtract the two like fractions:
35/210 - 45/210 = 35 - 45/210 = -10/210 - After reducing the fraction, the answer is -1/21
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