Subtract 30/36 from 72/21
1st number: 3 9/21, 2nd number: 30/36
72/21 - 30/36 is 109/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
72/21 = 72 × 12/21 × 12 = 864/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252 - Subtract the two like fractions:
864/252 - 210/252 = 864 - 210/252 = 654/252 - After reducing the fraction, the answer is 109/42
- In mixed form: 225/42
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