Subtract 18/21 from 28/35
28/35 - 18/21 is -2/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
28/35 = 28 × 3/35 × 3 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Subtract the two like fractions:
84/105 - 90/105 = 84 - 90/105 = -6/105 - After reducing the fraction, the answer is -2/35
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