Subtract 21/75 from 18/20
18/20 - 21/75 is 31/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 75 is 300
Next, find the equivalent fraction of both fractional numbers with denominator 300 - For the 1st fraction, since 20 × 15 = 300,
18/20 = 18 × 15/20 × 15 = 270/300 - Likewise, for the 2nd fraction, since 75 × 4 = 300,
21/75 = 21 × 4/75 × 4 = 84/300 - Subtract the two like fractions:
270/300 - 84/300 = 270 - 84/300 = 186/300 - After reducing the fraction, the answer is 31/50
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