Subtract 21/80 from 72/84
72/84 - 21/80 is 333/560.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
72/84 = 72 × 20/84 × 20 = 1440/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Subtract the two like fractions:
1440/1680 - 441/1680 = 1440 - 441/1680 = 999/1680 - After reducing the fraction, the answer is 333/560
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