Subtract 21/84 from 7/80
7/80 - 21/84 is -13/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 84 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
7/80 = 7 × 21/80 × 21 = 147/1680 - Likewise, for the 2nd fraction, since 84 × 20 = 1680,
21/84 = 21 × 20/84 × 20 = 420/1680 - Subtract the two like fractions:
147/1680 - 420/1680 = 147 - 420/1680 = -273/1680 - After reducing the fraction, the answer is -13/80
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