Subtract 21/80 from 1/2
1/2 - 21/80 is 19/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 2 × 40 = 80,
1/2 = 1 × 40/2 × 40 = 40/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Subtract the two like fractions:
40/80 - 21/80 = 40 - 21/80 = 19/80
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