Subtract 21/42 from 72/36
1st number: 2 0/36, 2nd number: 21/42
72/36 - 21/42 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
72/36 = 72 × 7/36 × 7 = 504/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
21/42 = 21 × 6/42 × 6 = 126/252 - Subtract the two like fractions:
504/252 - 126/252 = 504 - 126/252 = 378/252 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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