Subtract 21/18 from 30/60
1st number: 30/60, 2nd number: 1 3/18
30/60 - 21/18 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 60 × 3 = 180,
30/60 = 30 × 3/60 × 3 = 90/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Subtract the two like fractions:
90/180 - 210/180 = 90 - 210/180 = -120/180 - After reducing the fraction, the answer is -2/3
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