Subtract 42/45 from 72/21
1st number: 3 9/21, 2nd number: 42/45
72/21 - 42/45 is 262/105.
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,
42/45 = 42 × 7/45 × 7 = 294/315 - Subtract the two like fractions:
1080/315 - 294/315 = 1080 - 294/315 = 786/315 - After reducing the fraction, the answer is 262/105
- In mixed form: 252/105
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