Subtract 20/50 from 7/21
7/21 - 20/50 is -1/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 50 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 21 × 50 = 1050,
7/21 = 7 × 50/21 × 50 = 350/1050 - Likewise, for the 2nd fraction, since 50 × 21 = 1050,
20/50 = 20 × 21/50 × 21 = 420/1050 - Subtract the two like fractions:
350/1050 - 420/1050 = 350 - 420/1050 = -70/1050 - After reducing the fraction, the answer is -1/15
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