Subtract 30/40 from 28/80
28/80 - 30/40 is -2/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
28/80 = 28 × 1/80 × 1 = 28/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
30/40 = 30 × 2/40 × 2 = 60/80 - Subtract the two like fractions:
28/80 - 60/80 = 28 - 60/80 = -32/80 - After reducing the fraction, the answer is -2/5
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