Subtract 21/50 from 72/81
72/81 - 21/50 is 211/450.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 50 is 4050
Next, find the equivalent fraction of both fractional numbers with denominator 4050 - For the 1st fraction, since 81 × 50 = 4050,
72/81 = 72 × 50/81 × 50 = 3600/4050 - Likewise, for the 2nd fraction, since 50 × 81 = 4050,
21/50 = 21 × 81/50 × 81 = 1701/4050 - Subtract the two like fractions:
3600/4050 - 1701/4050 = 3600 - 1701/4050 = 1899/4050 - After reducing the fraction, the answer is 211/450
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