Subtract 28/80 from 9/30
9/30 - 28/80 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 30 × 8 = 240,
9/30 = 9 × 8/30 × 8 = 72/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
28/80 = 28 × 3/80 × 3 = 84/240 - Subtract the two like fractions:
72/240 - 84/240 = 72 - 84/240 = -12/240 - After reducing the fraction, the answer is -1/20
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