4 or 5 digit code with alphabet

[ska7945]

How many codes are possible when using alphabet to make 4 digit or 5 digit code?

a.26(26)^4
b.27(26)^4
c.26(26)^4
d.27(26)^5
e.26^5

[vittalgmat]

# of ways a 4 digit code can be created is 26^4.
(ie. 26 ways for each digit => 26*26*26*26.)

Similarly # of ways a 5 digit code can be created is 26^5

Since it is an OR, we add these two
26^4 + 26^5
= 26^4(1 + 26)
= 27 * 26^4

So B is the answer

[vittalgmat]

# of ways a 4 digit code can be created is 26^4.
(ie. 26 ways for each digit => 26*26*26*26.)

Similarly # of ways a 5 digit code can be created is 26^5

Since it is an OR, we add these two
26^4 + 26^5
= 26^4(1 + 26)
= 27 * 26^4

So B is the answer

[stop@800]

Yes B should be the OA

26^4 + 26^5