PCEP Practice Test 15 — 15 Questions

Question 1

Refer to the exhibit. What does the else clause of the inner for loop do?

Accepted Answer

Executes if the inner loop completes without break, meaning no even number in the row.. The else clause of a for loop in Python executes only when the loop completes normally, i.e., without encountering a break statement. In this nested loop, the inner for iterates over elements of a row; if no even number is found (no break), the else triggers, indicating the row has no even numbers. This is why option C is correct.

Answer

Executes if the outer loop condition is false.

Answer

Executes if the inner loop is broken, meaning an even number was found.

Answer

Executes after each iteration of the inner loop.

Question 2

Refer to the exhibit. What is the output of the Python code?

Accepted Answer

abcabcabc. The code `print('abc' * 3)` uses the multiplication operator on a string. In Python, multiplying a string by an integer repeats the string that many times, concatenating the copies without any separator. Therefore, `'abc' * 3` produces the string `'abcabcabc'`, which is printed. The correct output is `abcabcabc` (without quotes).

Answer

['abc', 'abc', 'abc']

Answer

abcabc abc

Answer

abc abc abc

Question 3

A developer accidentally wrote: print('Hello' + 5). What happens?

Accepted Answer

It raises a TypeError. In Python, the `+` operator is overloaded for string concatenation only when both operands are strings. Attempting to concatenate a string (`'Hello'`) with an integer (`5`) violates Python's strong dynamic typing rules, which do not perform implicit type coercion for this operation. This raises a `TypeError` with a message like 'can only concatenate str (not "int") to str'.

Answer

It prints 'Hello' and ignores the 5

Answer

It prints a warning but still runs

Answer

It prints 'Hello5'

Question 4

Which THREE of the following statements about Python operators are correct?

Accepted Answer

The ** operator performs exponentiation.. Option A is correct because in Python the ** operator is the exponentiation operator, so 2 ** 3 evaluates to 8. Option B is correct because // performs floor division, discarding the fractional part, and returns an int when both operands are ints (e.g., 7 // 2 gives 3). Option C is correct because the / operator performs true division and always returns a float, even for evenly divisible integers (e.g., 4 / 2 gives 2.0). Option D is not correct because + cannot concatenate a string and an integer directly; doing so raises a TypeError unless the integer is converted with str(). Option E is not correct because % is the modulo operator and returns the remainder of a division, not the quotient.

Answer

The + operator can be used to concatenate strings and integers.

Answer

The % operator returns the quotient.

Question 5

What happens when you try to modify a tuple?

t = (1, 2, 3)
t[0] = 0

Accepted Answer

A TypeError is raised. Tuples are immutable, so trying to assign to an index raises a TypeError.

Answer

A IndexError is raised

Answer

The tuple becomes (0, 2, 3)

Answer

The code runs without error

Question 6

Which THREE of the following are correct ways to create a list containing the numbers 1, 2, 3? (Choose three.)

Accepted Answer

[x for x in range(1,4)]. Option A, `[x for x in range(1,4)]`, is correct because a list comprehension over `range(1,4)` iterates x = 1, 2, 3 (the stop value 4 is exclusive) and builds a list `[1, 2, 3]`. Option C, `list((1, 2, 3))`, is correct because the `list()` constructor converts the tuple `(1, 2, 3)` into a new list containing those same elements. Option D, `[1, 2, 3]`, is correct because it is a direct list literal that already contains the numbers 1, 2, and 3. Option B, `(1, 2, 3)`, does not belong because parentheses create a tuple, not a list. Option E, `{1, 2, 3}`, does not belong because curly braces create a set, which is unordered and not a list.

Answer

(1, 2, 3)

Answer

{1, 2, 3}

Question 7

Which THREE of the following are Python built-in data types?

Accepted Answer

bool. Option B (bool) is a Python built-in type used for the two truth values True and False, and it is a subclass of int. Option D (float) is a built-in numeric type representing double-precision floating-point numbers such as 3.14. Option E (int) is a built-in numeric type for arbitrary-precision integers, so it is correct as well. Option A (array) is not a built-in type; it is provided by the standard-library array module (or similar third-party libraries), so it must be imported rather than being built in. Option C (char) is not a Python built-in type at all; Python represents single characters as strings of length 1, and there is no char type.

Answer

array

Answer

char

Question 8

A function is defined as:
def add(a, b=5):
    return a + b
What is the result of add(10)?

Accepted Answer

15. The function `add(a, b=5)` defines a default value of 5 for parameter `b`. When called as `add(10)`, the argument 10 is assigned to `a`, and `b` uses its default value of 5. The function returns `10 + 5 = 15`, making option C correct.

Answer

10

Answer

5

Answer

Error

Question 9

Order the steps to debug a Python script using print statements.

Accepted Answer

1. Insert print statements, 2. Run the script, 3. Analyze the output, 4. Remove print statements. Debugging with print involves inserting prints, running, analyzing, and cleaning up.

Answer

1. Insert print statements, 2. Remove print statements, 3. Run the script, 4. Analyze the output

Answer

1. Run the script, 2. Insert print statements, 3. Analyze the output, 4. Remove print statements

Answer

1. Analyze the output, 2. Insert print statements, 3. Run the script, 4. Remove print statements

Question 10

A function is defined as: def min_max(nums): return min(nums), max(nums). What type of value does it return?

Accepted Answer

A tuple. The function `min_max` uses `return min(nums), max(nums)`, which is a comma-separated list of expressions. In Python, when multiple values are returned separated by commas, they are automatically packed into a tuple. Therefore, the function returns a tuple containing the minimum and maximum values.

Answer

A set

Answer

A dictionary

Answer

A list

Question 11

What is the result of the following expression?

d = {'a': 1}
d.get('b', 0)

Accepted Answer

0. The `get()` method on a dictionary returns the value for the given key if it exists; otherwise, it returns the default value provided as the second argument. Since key `'b'` is not in dictionary `d`, the method returns `0` (the specified default). Option A is correct because `d.get('b', 0)` explicitly supplies a default of `0`.

Answer

None

Answer

KeyError

Answer

1

Question 12

Which THREE of the following are valid ways to create a list with elements 1, 2, 3? (Choose Three)

Accepted Answer

[1,2,3]. Option A, [1,2,3], is correct because a list literal enclosed in square brackets directly creates a list with the elements 1, 2, and 3 in order. Option B, list(range(1,4)), is correct because range(1,4) generates the integers 1, 2, 3 (the stop value 4 is exclusive), and wrapping it in the list() constructor materializes them as a list. Option D, [x for x in range(1,4)], is correct because this list comprehension iterates over range(1,4), producing the values 1, 2, 3 and collecting them into a new list. Option C, (1,2,3), is not correct because parentheses create a tuple, not a list, and tuples are immutable and of a different type. Option E, {1,2,3}, is not correct because curly braces create a set, which is unordered and contains no duplicates, so it is not a list.

Answer

(1,2,3)

Answer

{1,2,3}

Question 13

After executing: a = 5; b = 2; c = a // b; d = a % b; e = a ** b. What is the value of (c + d) * 2 - e?

Accepted Answer

-19. After executing the code, a=5, b=2, c=5//2=2 (floor division), d=5%2=1 (remainder), e=5**2=25 (exponentiation). Then (c+d)*2-e = (2+1)*2-25 = 3*2-25 = 6-25 = -19. Option B is correct because it matches this calculation.

Answer

-20

Answer

-11

Answer

-15

Question 14

A system administrator writes a script to monitor disk usage. The script reads a percentage from a file as a string, e.g., "100". The code:

usage = open("usage.txt").read().strip()
if usage > 80:
    print("Warning: disk usage high")
else:
    print("Disk usage OK")

Even when usage.txt contains "100", the script prints "Disk usage OK". The admin expected "Warning". What is the problem and how to fix?

Accepted Answer

The file reading returns a string; convert usage to int before comparison.. The `read()` method returns the file content as a string. In Python, comparing a string to an integer with `>` performs lexicographic (character-by-character) comparison, not numeric comparison. For example, `"100" > 80` evaluates to `False` because `"1"` (ASCII 49) is less than `80` (integer), so the condition fails and the script prints "Disk usage OK". Converting the string to an integer with `int(usage)` before the comparison ensures numeric comparison works as intended.

Answer

The comparison operator > is incorrect; use >= instead.

Answer

The file is not properly closed; use with statement.

Answer

The strip() method removes newlines but not spaces; usage may have extra spaces.