briozeal wrote:

The addition problem above shows four of the 24 different integers that can be formed by using each of the digits 1,2,3 & 4 exactly once in each integer. what is the sum of these 24 integers ?

A. 24000

B. 26664

C. 40440

D. 60000

E. 66660

How come there are only 24 possible combinations ? when I think there could be only 16 ??

Is it a combination questions ???

I don't how to call this type of question

But some combo definitely using here

There is 4! ways to place 4 integers 4!=24. Hence there is 24 different intgers consisting of 4 digits!

1234 2134

1342 2341

1423 2431

1243 2143

1324

1243

And so on!But you don't need to draw every possible combination of digits

You need only to remember that 4 digits may be arranged in 4!ways which is equal to 4*3*2*1=24 .For Example 5 digits may be arranged 5! ways 5!=5*4*3*2*1=120 Hope his helps!

By the way the answer Is E!I think

Later will explain if you need