Subtract 42/16 from 21/80
1st number: 21/80, 2nd number: 2 10/16
21/80 - 42/16 is -189/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
42/16 = 42 × 5/16 × 5 = 210/80 - Subtract the two like fractions:
21/80 - 210/80 = 21 - 210/80 = -189/80
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