Subtract 21/10 from 30/80
1st number: 30/80, 2nd number: 2 1/10
30/80 - 21/10 is -69/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 10 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80 - Likewise, for the 2nd fraction, since 10 × 8 = 80,
21/10 = 21 × 8/10 × 8 = 168/80 - Subtract the two like fractions:
30/80 - 168/80 = 30 - 168/80 = -138/80 - After reducing the fraction, the answer is -69/40
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