Subtract 3/84 from 20/40
20/40 - 3/84 is 13/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 84 × 10 = 840,
3/84 = 3 × 10/84 × 10 = 30/840 - Subtract the two like fractions:
420/840 - 30/840 = 420 - 30/840 = 390/840 - After reducing the fraction, the answer is 13/28
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