The total number of possible 7-place license plates are 67600000.
Given: A7-plate license plate. 2 places are for letters and 5 places are for numbers. To find how many different 7-plate license plates are possible
Let's solve the given problem:
The license plate has 7 places. 2 places are for letters and the remaining 5 places are for numbers.
Combination of letters: As there are no restrictions given in the question, so the first letter can be any alphabet out of the 26 alphabets (A, B, C, D, ......... Z). So the first place for the letter can be filled in ²⁶C₁ ways that are 26 ways. Also for the second place, as the letters can repeat so it can be filled in ²⁶C₁ ways too which are 26 ways. Therefore, the possible ways in which the place for two letters can be filled is 26 × 26 ways = 676 ways.
Combination of numbers: As there are no restrictions given in the question so the first number can be any of the numbers out of the 10 numbers (10, 1, 2, 3, ....... 9). So the first number can be filled in ¹⁰C₁ = 10 ways. Similarly, as the numbers can repeat so the 2nd, 3rd, 4th and 5th numbers can be filled in ¹⁰C₁ ways that all the other places can be filled in 10 ways each. Therefore the total number of ways in which the place for 5 numbers can be filled is 10 × 10 × 10 × 10 × 10 ways = 100000 ways.
Therefore, the total number of ways in which the 7-place license plate can fill are: Total possible ways in which the two letters can be filled × Total possible ways in which the 5 number places can be filled
= 676 × 100000
= 67600000 ways
Hence the total number of possible 7-place license plates are 67600000.
