Subtract 18/35 from 7/21
7/21 - 18/35 is -19/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
18/35 = 18 × 3/35 × 3 = 54/105 - Subtract the two like fractions:
35/105 - 54/105 = 35 - 54/105 = -19/105
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