Subtract 4/80 from 1/21
1/21 - 4/80 is -1/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
1/21 = 1 × 80/21 × 80 = 80/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
4/80 = 4 × 21/80 × 21 = 84/1680 - Subtract the two like fractions:
80/1680 - 84/1680 = 80 - 84/1680 = -4/1680 - After reducing the fraction, the answer is -1/420
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