Subtract 15/30 from 28/84
28/84 - 15/30 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
28/84 = 28 × 5/84 × 5 = 140/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
15/30 = 15 × 14/30 × 14 = 210/420 - Subtract the two like fractions:
140/420 - 210/420 = 140 - 210/420 = -70/420 - After reducing the fraction, the answer is -1/6
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