Subtract 30/50 from 21/84
21/84 - 30/50 is -7/20.
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,
21/84 = 21 × 25/84 × 25 = 525/2100 - Likewise, for the 2nd fraction, since 50 × 42 = 2100,
30/50 = 30 × 42/50 × 42 = 1260/2100 - Subtract the two like fractions:
525/2100 - 1260/2100 = 525 - 1260/2100 = -735/2100 - After reducing the fraction, the answer is -7/20
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