Subtract 15/42 from 12/70
12/70 - 15/42 is -13/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
12/70 = 12 × 3/70 × 3 = 36/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
15/42 = 15 × 5/42 × 5 = 75/210 - Subtract the two like fractions:
36/210 - 75/210 = 36 - 75/210 = -39/210 - After reducing the fraction, the answer is -13/70
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