Question 1easymultiple choice
Full question →- A
Raises TypeError
Incompatible types for +.
- B
Prints 30
Why wrong: No implicit conversion.
- C
Prints 10 + 20
Why wrong: Not a string representation.
- D
Prints 1020
Why wrong: Only if both were strings.
Question 20 of 510
PCEP Practice Question: Data Types, Variables, Basic I/O and Operators
This PCEP practice question tests your understanding of data types, variables, basic i/o and operators. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A beginner writes: x = '10'; y = 20; print(x + y). What happens?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Raises TypeError
Option A is correct because Python's type system does not allow implicit concatenation of a string and an integer. The variable `x` is a string (`'10'`), and `y` is an integer (`20`). The `+` operator with these types triggers a `TypeError: unsupported operand type(s) for +: 'int' and 'str'` (or vice versa), as Python refuses to guess the programmer's intent.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Raises TypeError
Why this is correct
Incompatible types for +.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Prints 30
Why it's wrong here
No implicit conversion.
- ✗
Prints 10 + 20
Why it's wrong here
Not a string representation.
- ✗
Prints 1020
Why it's wrong here
Only if both were strings.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often expect Python to behave like JavaScript or PHP, which implicitly coerce types, but Python strictly requires explicit type conversion for mixed-type operations.
Detailed technical explanation
How to think about this question
Under the hood, Python's `+` operator is overloaded: for numeric types it performs arithmetic addition, for sequences (like strings) it performs concatenation. When types differ, Python's dynamic type system does not automatically coerce; it raises a TypeError to avoid ambiguity. In real-world code, this forces explicit conversion via `int(x)` or `str(y)`, preventing silent bugs in data processing pipelines.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Data Types, Variables, Basic I/O and Operators — study guide chapter
Learn the concepts, then practise the questions
- →
Data Types, Variables, Basic I/O and Operators practice questions
Targeted practice on this topic area only
- →
All PCEP questions
510 questions across all exam domains
- →
Certified Entry-Level Python Programmer PCEP study guide
Full concept coverage aligned to exam objectives
- →
PCEP practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCEP practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Computer Programming and Python Fundamentals practice questions
Practise PCEP questions linked to Computer Programming and Python Fundamentals.
Data Types, Variables, Basic I/O and Operators practice questions
Practise PCEP questions linked to Data Types, Variables, Basic I/O and Operators.
Control Flow, Loops, Lists and Logic practice questions
Practise PCEP questions linked to Control Flow, Loops, Lists and Logic.
Functions, Tuples, Dictionaries and Exceptions practice questions
Practise PCEP questions linked to Functions, Tuples, Dictionaries and Exceptions.
PCEP fundamentals practice questions
Practise PCEP questions linked to PCEP fundamentals.
PCEP scenario practice questions
Practise PCEP questions linked to PCEP scenario.
PCEP troubleshooting practice questions
Practise PCEP questions linked to PCEP troubleshooting.
Practice this exam
Start a free PCEP practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this PCEP question test?
Data Types, Variables, Basic I/O and Operators — This question tests Data Types, Variables, Basic I/O and Operators — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Raises TypeError — Option A is correct because Python's type system does not allow implicit concatenation of a string and an integer. The variable `x` is a string (`'10'`), and `y` is an integer (`20`). The `+` operator with these types triggers a `TypeError: unsupported operand type(s) for +: 'int' and 'str'` (or vice versa), as Python refuses to guess the programmer's intent.
What should I do if I get this PCEP question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More PCEP practice questions
- Which THREE of the following statements about Python data types are correct? (Choose three.)
- A developer writes the following code snippet: for i in range(3): for j in range(2): if i == j:…
- Order the steps to write a for loop that iterates over a range of numbers.
- Arrange the steps to slice a list in Python.
- Order the steps to create and use a list in Python.
- Arrange the steps to write and run a Python script from the command line in the correct order.
Last reviewed: Jun 11, 2026
This PCEP practice question is part of Courseiva's free Python Institute certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCEP exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.