Subtract 20/50 from 18/84
18/84 - 20/50 is -13/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 50 is 2100
Next, find the equivalent fraction of both fractional numbers with denominator 2100 - For the 1st fraction, since 84 × 25 = 2100,
18/84 = 18 × 25/84 × 25 = 450/2100 - Likewise, for the 2nd fraction, since 50 × 42 = 2100,
20/50 = 20 × 42/50 × 42 = 840/2100 - Subtract the two like fractions:
450/2100 - 840/2100 = 450 - 840/2100 = -390/2100 - After reducing the fraction, the answer is -13/70
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