PCEP Practice Test 25 — 15 Questions

Question 1

Refer to the exhibit. The code used is: name = input('Enter name: '); print('Hello', name). What will be printed if the user enters 'Alice'?

Accepted Answer

Hello Alice. The `input()` function captures the user's typed input as a string, and the `print()` function outputs the string 'Hello ' followed by the value of the `name` variable. When the user enters 'Alice', `name` becomes 'Alice', so the output is 'Hello Alice'.

Answer

Hello Bob

Answer

Error

Answer

Hello name

Question 2

A program uses a for loop to double each element in a list: numbers = [1, 2, 3, 4, 5]; for num in numbers: num = num * 2. After execution, numbers remains unchanged. Why?

Accepted Answer

Reassigning num does not modify the original list element; you need to modify via index.. In Python, the loop variable `num` is a reference to each element in the list, but reassigning `num` (e.g., `num = num * 2`) merely rebinds the local variable to a new integer object; it does not modify the original list element. To change the list in place, you must access elements by their index, such as `numbers[i] = numbers[i] * 2`.

Answer

The assignment creates a new list, leaving the original unchanged.

Answer

Lists are immutable; their elements cannot be changed.

Answer

The variable num is a copy of the list element.

Question 3

What is the output of the following code?

print('Hello'.upper())

Accepted Answer

HELLO. The `.upper()` string method in Python returns a new string with all lowercase letters converted to uppercase. The string `'Hello'` contains the characters 'H', 'e', 'l', 'l', 'o'; after applying `.upper()`, it becomes `'HELLO'`. The output is exactly `HELLO` without any additional characters.

Answer

hello

Answer

HELLO!

Answer

Hello

Question 4

A system administrator is automating server configuration using Python. She has a dictionary: config = {'host': 'localhost', 'port': 8080, 'debug': True}. She needs to add a new key 'timeout' with value 30 if it does not already exist, but only if the 'debug' key is False. If 'debug' is True, she should not add 'timeout'. Additionally, she wants to ensure that the ordering of keys in the dictionary remains stable (insertion order). Which code snippet correctly implements this logic?

Accepted Answer

if not config.get('debug'): config.setdefault('timeout', 30). `config.get('debug')` returns `True` (the value of the 'debug' key), and `not True` evaluates to `False`, so the `if` block is not entered — thus 'timeout' is not added. If 'debug' were `False`, `not False` would be `True`, and `config.setdefault('timeout', 30)` would add the key only if it did not already exist, preserving insertion order (Python 3.7+ guarantees dict order).

Answer

if config.get('debug') == False: config.update({'timeout': 30})

Answer

if config['debug']: config['timeout'] = 30 else: pass

Answer

if config.setdefault('debug', False) == False: config['timeout'] = 30

Question 5

A script uses 'import math' then calls 'math.sqrt(-1)'. What is the outcome?

Accepted Answer

ValueError. `math.sqrt()` in Python's math module does not support negative arguments; it raises a `ValueError` when given a negative number, as the function is designed for real numbers only. The error message is 'math domain error', indicating the input is outside the domain of the mathematical function.

Answer

NaN

Answer

A complex number

Answer

AttributeError

Question 6

What is the result of the following expression? 3 + 4 * 2 ** 3 // 5

Accepted Answer

9. The expression follows Python's operator precedence: exponentiation (`**`) has the highest precedence, then multiplication (`*`) and floor division (`//`) are evaluated left to right, and finally addition (`+`). First, `2 ** 3` computes to 8. Then `4 * 8` gives 32, and `32 // 5` yields 6 (floor division truncates toward negative infinity, but here it's positive). Finally, `3 + 6` equals 9. Thus, option A is correct.

Answer

7

Answer

6

Answer

11

Question 7

A developer writes a program to calculate the average of three numbers: a=10; b=20; c=30; avg = a + b + c / 3; print(avg). What is the output?

Accepted Answer

40.0. The expression `a + b + c / 3` follows Python's operator precedence: division (`/`) has higher precedence than addition (`+`), so `c / 3` is evaluated first (30 / 3 = 10.0), then the additions are performed left to right: 10 + 20 + 10.0 = 40.0. The result is a float because division always returns a float in Python 3.

Answer

20.0

Answer

10.0

Answer

60.0

Question 8

What is the output of: print(10 // 3, 10 % 3)?

Accepted Answer

3 1. The // operator performs floor division, returning the integer quotient (10 // 3 = 3), and the % operator returns the remainder (10 % 3 = 1). The print function outputs these two values separated by a space.

Answer

3.3333 1

Answer

3.0 1.0

Answer

1 3

Question 9

A developer needs to check if a number is positive and even. Which conditional expression is correct?

Accepted Answer

if num > 0 and num % 2 == 0:. Python uses the keyword `and` for logical conjunction, and the equality operator is `==` (not `=`). The expression `num > 0 and num % 2 == 0` correctly checks that `num` is both greater than zero and divisible by 2 with no remainder, which defines a positive even number.

Answer

if num > 0 & num % 2 == 0:

Answer

if num > 0 and num % 2 = 0:

Answer

if num > 0 && num % 2 == 0:

Question 10

Which of the following statements about Python indentation is true?

Accepted Answer

Indentation must be consistent within a block.. Python enforces consistent indentation within a block to define the scope of statements. Unlike many languages that use braces, Python relies on the indentation level to group statements, and any inconsistency (e.g., mixing spaces and tabs or varying the number of spaces) will raise an IndentationError.

Answer

Indentation is optional but recommended.

Answer

You can mix tabs and spaces freely.

Answer

Indentation only matters for loops and conditionals.

Question 11

A junior developer is working on a script that processes user data. The script reads a CSV file into a list of dictionaries. Each dictionary represents a user with keys 'name', 'age', and 'email'. The developer needs to filter out users under 18 and store their names in a list. The current code is:

users = [{'name': 'Alice', 'age': 17, 'email': 'alice@example.com'}, {'name': 'Bob', 'age': 22, 'email': 'bob@example.com'}]

minors = []
for user in users:
    if user['age'] < 18:
        minors.append(user['name'])

print(minors)

The code works, but the senior developer says it is not idiomatic and suggests a more concise solution. Which of the following approaches is the best replacement?

Accepted Answer

minors = [user['name'] for user in users if user['age'] < 18]. It uses a list comprehension to directly extract the 'name' field from each user dictionary where the age is under 18, making the code concise and Pythonic. The original code works but is verbose; list comprehensions are the idiomatic Python approach for transforming and filtering iterables in a single readable line.

Answer

minors = []
for i in range(len(users)):
    if users[i]['age'] < 18:
        minors.append(users[i]['name'])

Answer

minors = [user for user in users if user['age'] < 18]

Answer

minors = list(map(lambda u: u['name'], filter(lambda u: u['age'] < 18, users)))

Question 12

A developer writes: a = 3; b = 4; c = a + b / 2. What is the value of c?

Accepted Answer

5.0. In Python, the division operator `/` always returns a float, and operator precedence dictates that division is performed before addition. Thus, `b / 2` evaluates to `4 / 2 = 2.0`, then `a + 2.0` yields `3 + 2.0 = 5.0`. Option D is correct because the result is a float value of 5.0.

Answer

3

Answer

3.5

Answer

5

Question 13

A programmer writes: x = 5; y = 2; result = x / y. What is the type of result?

Accepted Answer

float. In Python 3, the division operator (/) always returns a floating-point number, even if both operands are integers. Since x and y are both integers (5 and 2), the result of 5 / 2 is 2.5, which is of type float. Therefore, option B is correct.

Answer

int

Answer

str

Answer

complex

Question 14

A developer writes the following code snippet:
for i in range(3):
    for j in range(2):
        if i == j:
            break
    else:
        print(i, 'outer')
What is the output?

Accepted Answer

2 outer. The code uses nested loops with a `for-else` construct. The `else` block executes only if the inner loop completes without a `break`. When `i == j`, the `break` exits the inner loop, skipping the `else`. For `i=0`, `j=0` triggers `break`; for `i=1`, `j=1` triggers `break`; for `i=2`, the inner loop runs `j=0,1` without any `i==j` (since 2 != 0 and 2 != 1), so the `else` executes, printing `2 outer`. Thus, only option B is correct.

Answer

0 outer
2 outer

Answer

0 outer
1 outer
2 outer

Answer

No output

Question 15

Which TWO of the following are valid Python data types?

Accepted Answer

str. Option B (str) is correct because str is a built-in Python data type used to represent immutable sequences of Unicode characters, such as 'hello'. Option D (int) is correct because int is a built-in Python data type for arbitrary-precision integers, e.g., 42. Option A (real) is not a Python built-in type; Python uses float for floating-point numbers. Option C (array) is not a built-in Python data type, though the array module provides an array class. Option E (char) is not a Python data type; Python represents single characters as strings of length 1.

Answer

real

Answer

array

Answer

char