Subtract 8/21 from 5/70
5/70 - 8/21 is -13/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
5/70 = 5 × 3/70 × 3 = 15/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
8/21 = 8 × 10/21 × 10 = 80/210 - Subtract the two like fractions:
15/210 - 80/210 = 15 - 80/210 = -65/210 - After reducing the fraction, the answer is -13/42
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