Question 1

Q1. Consider the following options for characters in setting a password:

• Digits = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }
• Letters = { a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z }
• Special characters = { *, &, $, # }

Compute the number of passwords possible that satisfy these conditions:

• Password must be of length 5.
• Characters can be special characters, digits, or letters.
• Characters may be repeated.

Your Answer:

Question 1 options:

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Question 2

Q2. Consider the following options for characters in setting a password:

• Digits = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }
• Letters = { a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z }
• Special characters = { *, &, $, # }

Compute the number of passwords possible that satisfy these conditions:

• Password must be of length 8.
• Characters can be special characters, digits, or letters.
• The first character must be a letter.
• Characters may be repeated.

Your Answer:

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Question 3

Q4. Suppose account numbers for an internet service provider consist of alpha-numeric characters. The first character is a digit (0 through 9). The next 2 characters are capital letters (A through Z) and the last four characters are digits.

How many account numbers are possible if no digit appears more than once?

Your Answer:

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Question 4

Q5. If 17 students from a 1st-grade class are lining up to enter the cafeteria line for lunch, how many ways are there to line up the 17 students?

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Question 5

Q10. A ternary string is an ordered string of characters which consists of digits (0,1, or 2). For example, the ternary string 2122010 consists of exactly 2 zero's, 2 one's and 3 two's; another ternary string meeting these conditions is 0021221.

How many ternary strings are there with exactly 3 zero's, 5 one's and 4 two's?

Your Answer:

Question 5 options:

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