Subtract 21/18 from 18/30
1st number: 18/30, 2nd number: 1 3/18
18/30 - 21/18 is -17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
18/30 = 18 × 3/30 × 3 = 54/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
54/90 - 105/90 = 54 - 105/90 = -51/90 - After reducing the fraction, the answer is -17/30
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