Subtract 18/72 from 21/12
1st number: 1 9/12, 2nd number: 18/72
21/12 - 18/72 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 12 × 6 = 72,
21/12 = 21 × 6/12 × 6 = 126/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
18/72 = 18 × 1/72 × 1 = 18/72 - Subtract the two like fractions:
126/72 - 18/72 = 126 - 18/72 = 108/72 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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