Subtract 8/15 from 18/21
18/21 - 8/15 is 34/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
8/15 = 8 × 7/15 × 7 = 56/105 - Subtract the two like fractions:
90/105 - 56/105 = 90 - 56/105 = 34/105
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