Subtract 21/20 from 30/80
1st number: 30/80, 2nd number: 1 1/20
30/80 - 21/20 is -27/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 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 20 × 4 = 80,
21/20 = 21 × 4/20 × 4 = 84/80 - Subtract the two like fractions:
30/80 - 84/80 = 30 - 84/80 = -54/80 - After reducing the fraction, the answer is -27/40
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