Subtract 40/70 from 8/42
8/42 - 40/70 is -8/21.
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,
8/42 = 8 × 5/42 × 5 = 40/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
40/70 = 40 × 3/70 × 3 = 120/210 - Subtract the two like fractions:
40/210 - 120/210 = 40 - 120/210 = -80/210 - After reducing the fraction, the answer is -8/21
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