Subtract 3/84 from 21/35
21/35 - 3/84 is 79/140.
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,
3/84 = 3 × 5/84 × 5 = 15/420 - Subtract the two like fractions:
252/420 - 15/420 = 252 - 15/420 = 237/420 - After reducing the fraction, the answer is 79/140
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