Subtract 21/42 from 72/18
1st number: 4 0/18, 2nd number: 21/42
72/18 - 21/42 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
72/18 = 72 × 7/18 × 7 = 504/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Subtract the two like fractions:
504/126 - 63/126 = 504 - 63/126 = 441/126 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
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