Subtract 20/50 from 21/75
21/75 - 20/50 is -3/25.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 50 is 150
Next, find the equivalent fraction of both fractional numbers with denominator 150 - For the 1st fraction, since 75 × 2 = 150,
21/75 = 21 × 2/75 × 2 = 42/150 - Likewise, for the 2nd fraction, since 50 × 3 = 150,
20/50 = 20 × 3/50 × 3 = 60/150 - Subtract the two like fractions:
42/150 - 60/150 = 42 - 60/150 = -18/150 - After reducing the fraction, the answer is -3/25
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