What is the value of \( \frac{27!}{25!\cdot2!}-\frac{26!}{24!\cdot2!} \)?

Correct answer: 26

Since \(27!=27\times26\times25!\), \(\frac{27!}{25!\cdot2!}=\frac{27\times26}{2}=351\). Similarly, \(\frac{26!}{24!\cdot2!}=\frac{26\times25}{2}=325\). Hence, the value is \(351-325=26\). Although 25 occurs as a factor in the second term, it is not the difference. Exam tip: In factorial fractions, expand the larger factorial only up to the smaller factorial and cancel common factors first.