Subtract 18/20 from 21/25
21/25 - 18/20 is -3/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 20 is 100
Next, find the equivalent fraction of both fractional numbers with denominator 100 - For the 1st fraction, since 25 × 4 = 100,
21/25 = 21 × 4/25 × 4 = 84/100 - Likewise, for the 2nd fraction, since 20 × 5 = 100,
18/20 = 18 × 5/20 × 5 = 90/100 - Subtract the two like fractions:
84/100 - 90/100 = 84 - 90/100 = -6/100 - After reducing the fraction, the answer is -3/50
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