Answer:
Given that only the first digit and a range of four possible numbers for the second digit of the four digit pin number are remembered, the number of different possible combinations are 400 (possible combinations)
Step-by-step explanation:
The given information are;
The number of digits contained in the pin = 4 digits
The number of digits that can be the first number = 1 (given that the first digit is 4)
The number of digits that can be the second number = 4 (6, 7, 8, or 9)
Therefore, we have;
The number of digits that can be the third number = 10 (0, 1, 2, 3, 4, 5, 6, 7, 8, or 9)
Similarly, the number of digits that can be the fourth number = 10
Therefore, the total number of possible combinations are;
1 × 4 × 10 × 10 = 400 possible combinations.
