Subtract 21/35 from 8/42
8/42 - 21/35 is -43/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 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 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Subtract the two like fractions:
40/210 - 126/210 = 40 - 126/210 = -86/210 - After reducing the fraction, the answer is -43/105
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