+0  
 
+1
46
6
avatar+201 

Given the four digits 2, 4, 6, and 7, how many different positive two-digit integers can be formed using these digits if a digit can be repeated in an integer?

 Apr 6, 2020
 #1
avatar+252 
+1

There are 4 possibilities for the first digit and 4 possibilities for the second. 4*4=16

 

smileysmileysmileysmileysmiley

 Apr 6, 2020
 #5
avatar
0

(2, 2), (2, 4), (2, 6), (2, 7), (4, 4), (4, 6), (4, 7), (6, 6), (6, 7), (7, 7), Total = 10

Guest Apr 6, 2020
 #6
avatar
0

Those are combinations. You need permutations which are: 4 x 4 = 16 

Guest Apr 6, 2020
 #2
avatar+201 
+2

Thanks!

 Apr 6, 2020
 #3
avatar+98 
+3

since all even numbers (2,4,6) will come is the last position, it can be filled in 3 ways, then the first place can be filled by 3 odd numbers + 2 even numbers (since one even number is fixed in the last position), the second position can be filled by 4 digits + 0 that is 5 digits, the third place can be filled by 4 digits and last place by 3, 

best answer plz I need it smiley

 Apr 6, 2020
 #4
avatar+201 
+1

Nice job!

 Apr 6, 2020

28 Online Users

avatar
avatar
avatar
avatar