Question
Question: How many different arrangements can be made out of the letters in the expansion A<sup>2</sup>B<sup>3...
How many different arrangements can be made out of the letters in the expansion A2B3C4, when written in full?
A
2!3!4!9!
B
2! + 3! + 4! (2! + 3! + 4!)
C
2! + 3! – 4
D
2!+3!+4!9!
Answer
2!+3!+4!9!
Explanation
Solution
‘A2 B3 C4’ A®2 times, B®3 times, C®4 times
Total arrangement = 2!3!4!(2+3+4)!=2!3!4!9!