Subtract 42/84 from 2/5
2/5 - 42/84 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 5 × 84 = 420,
2/5 = 2 × 84/5 × 84 = 168/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Subtract the two like fractions:
168/420 - 210/420 = 168 - 210/420 = -42/420 - After reducing the fraction, the answer is -1/10
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