Subtract 18/10 from 18/21
1st number: 18/21, 2nd number: 1 8/10
18/21 - 18/10 is -33/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Subtract the two like fractions:
180/210 - 378/210 = 180 - 378/210 = -198/210 - After reducing the fraction, the answer is -33/35
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