Subtract 42/84 from 21/35
21/35 - 42/84 is 1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Subtract the two like fractions:
252/420 - 210/420 = 252 - 210/420 = 42/420 - After reducing the fraction, the answer is 1/10
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