Subtract 30/50 from 21/42
21/42 - 30/50 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 50 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 42 × 25 = 1050,
21/42 = 21 × 25/42 × 25 = 525/1050 - Likewise, for the 2nd fraction, since 50 × 21 = 1050,
30/50 = 30 × 21/50 × 21 = 630/1050 - Subtract the two like fractions:
525/1050 - 630/1050 = 525 - 630/1050 = -105/1050 - After reducing the fraction, the answer is -1/10
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