Subtract 72/21 from 18/2
1st number: 9 0/2, 2nd number: 3 9/21
18/2 - 72/21 is 39/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
18/2 = 18 × 21/2 × 21 = 378/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Subtract the two like fractions:
378/42 - 144/42 = 378 - 144/42 = 234/42 - After reducing the fraction, the answer is 39/7
- In mixed form: 54/7
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