Subtract 21/75 from 20/72
20/72 - 21/75 is -1/450.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 75 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 72 × 25 = 1800,
20/72 = 20 × 25/72 × 25 = 500/1800 - Likewise, for the 2nd fraction, since 75 × 24 = 1800,
21/75 = 21 × 24/75 × 24 = 504/1800 - Subtract the two like fractions:
500/1800 - 504/1800 = 500 - 504/1800 = -4/1800 - After reducing the fraction, the answer is -1/450
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