Subtract 5/21 from 7/80
7/80 - 5/21 is -253/1680.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 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 21 × 80 = 1680,
5/21 = 5 × 80/21 × 80 = 400/1680 - Subtract the two like fractions:
147/1680 - 400/1680 = 147 - 400/1680 = -253/1680
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