Subtract 21/6 from 18/45
1st number: 18/45, 2nd number: 3 3/6
18/45 - 21/6 is -31/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 6 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
18/45 = 18 × 2/45 × 2 = 36/90 - Likewise, for the 2nd fraction, since 6 × 15 = 90,
21/6 = 21 × 15/6 × 15 = 315/90 - Subtract the two like fractions:
36/90 - 315/90 = 36 - 315/90 = -279/90 - After reducing the fraction, the answer is -31/10
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