Subtract 9/20 from 21/75
21/75 - 9/20 is -17/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 20 is 300
Next, find the equivalent fraction of both fractional numbers with denominator 300 - For the 1st fraction, since 75 × 4 = 300,
21/75 = 21 × 4/75 × 4 = 84/300 - Likewise, for the 2nd fraction, since 20 × 15 = 300,
9/20 = 9 × 15/20 × 15 = 135/300 - Subtract the two like fractions:
84/300 - 135/300 = 84 - 135/300 = -51/300 - After reducing the fraction, the answer is -17/100
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