Subtract 7/45 from 72/21
1st number: 3 9/21, 2nd number: 7/45
72/21 - 7/45 is 1031/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
72/21 = 72 × 15/21 × 15 = 1080/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
7/45 = 7 × 7/45 × 7 = 49/315 - Subtract the two like fractions:
1080/315 - 49/315 = 1080 - 49/315 = 1031/315 - In mixed form: 386/315
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