Subtract 21/45 from 18/12
1st number: 1 6/12, 2nd number: 21/45
18/12 - 21/45 is 31/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
18/12 = 18 × 15/12 × 15 = 270/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180 - Subtract the two like fractions:
270/180 - 84/180 = 270 - 84/180 = 186/180 - After reducing the fraction, the answer is 31/30
- In mixed form: 11/30
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