Solve the problem.
-If a license plate consists of four digits, how many different licenses could be created having at Least one digit repeated.
A) 10,000
B) 5040
C) 4960
D) 3024

Question

Quizplus · Accepted Answer

First, calculate the total number of possible license plates without any restrictions, which is $10^4 = 10,000$. Then, calculate the number of license plates with all unique digits, which is $10 \times 9 \times 8 \times 7 = 5040$. Subtracting the unique combinations from the total gives the number with at least one repeated digit: $10,000 - 5040 = 4960$.

Solve the Problem. -If a License Plate Consists of Four Digits, How Many