Subtract 27/42 from 21/35
21/35 - 27/42 is -3/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
27/42 = 27 × 5/42 × 5 = 135/210 - Subtract the two like fractions:
126/210 - 135/210 = 126 - 135/210 = -9/210 - After reducing the fraction, the answer is -3/70
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