Jack

10-10-2013, 10:27 AM

How many different 4-digit numbers can be formed using all of the following numbers?

0,1,1,9

(A) 4

(B) 12

(C) 16

(D) 24

thanks

0,1,1,9

(A) 4

(B) 12

(C) 16

(D) 24

thanks

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Jack

10-10-2013, 10:27 AM

How many different 4-digit numbers can be formed using all of the following numbers?

0,1,1,9

(A) 4

(B) 12

(C) 16

(D) 24

thanks

0,1,1,9

(A) 4

(B) 12

(C) 16

(D) 24

thanks

miranda

10-10-2013, 10:31 AM

In this case we have permutations since the order matters. Additionally we must divide the number of permutations by 2! Since the digit “1” appears twice.

Therefore the answer is \frac{^4P_{4}}{2!}=\frac{4!}{2!}=12 (B).

Therefore the answer is \frac{^4P_{4}}{2!}=\frac{4!}{2!}=12 (B).

Jack

10-10-2013, 10:32 AM

thank you!!

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