gmatbull wrote:
Supermarket D uses 2 tracking systems, S-1 and S-2. Both tracking systems use codes, each of which is an
ordered sequence of 6 characters. Each code for S-1 consists of 2 digits, each chosen from 0 through 9,
followed by 4 letters, each chosen from A through Z but excluding vowels (A, E, I, O, U) and Y. Each code
for S-2 consists of 4 digits, each chosen from 0 through 9, followed by 2 letters, each chosen from A through
Z but excluding vowels and Y. What fraction of the possible number of S-1 codes is the possible number of S-2 codes?
(Note: There are 20 letters from A through Z, excluding vowels and Y.)
Am sorry, no options, but will appreciate your contributions.
If the 1st tracking system uses different combinations (2D 4L), how can we have some common elements with
the 2nd tracking system, which uses (4D 2L)?
Question is not asking for common elements and as you rightly mentioned there cant be common codes as one is 2D,4L and other 4L, 2D
Instead, question is asking for the fraction that you get as : number of possible codes for S-2 / number of possible codes for S-1
(eg, say if possible number of S-1 is 100 then what fraction of it is S-2 which is 20. re-reading the question now should help
)
S-1 = 10*10*20*20*20*20
(Question has no restriction on repeating the digit or letter)
S-2 = 10*10*10*10*20*20
Hence, Ans = S-2/S-1 = 1/4
Hope it helps.