Subtract 9/20 from 21/50
21/50 - 9/20 is -3/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 20 is 100
Next, find the equivalent fraction of both fractional numbers with denominator 100 - For the 1st fraction, since 50 × 2 = 100,
21/50 = 21 × 2/50 × 2 = 42/100 - Likewise, for the 2nd fraction, since 20 × 5 = 100,
9/20 = 9 × 5/20 × 5 = 45/100 - Subtract the two like fractions:
42/100 - 45/100 = 42 - 45/100 = -3/100
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