Subtract 25/42 from 30/84
30/84 - 25/42 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
30/84 = 30 × 1/84 × 1 = 30/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
25/42 = 25 × 2/42 × 2 = 50/84 - Subtract the two like fractions:
30/84 - 50/84 = 30 - 50/84 = -20/84 - After reducing the fraction, the answer is -5/21
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