Subtract 42/5 from 21/80
1st number: 21/80, 2nd number: 8 2/5
21/80 - 42/5 is -651/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 5 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 5 × 16 = 80,
42/5 = 42 × 16/5 × 16 = 672/80 - Subtract the two like fractions:
21/80 - 672/80 = 21 - 672/80 = -651/80
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