Jack

10-10-2013, 11:27 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

View Full Version : sat math permutations

Jack

10-10-2013, 11:27 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, 11:31 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, 11:32 AM

thank you!!

Powered by vBulletin® Version 4.2.2 Copyright © 2019 vBulletin Solutions, Inc. All rights reserved.