Question 89 of 481
1Z0-811 Primitives, Strings and Operators Practice Question
A banking application uses a method to calculate interest: double calculateInterest(double balance) { return balance * 0.05; }. The method is called with an int argument: int accountBalance = 1000; double interest = calculateInterest(accountBalance); System.out.println(interest); The output is 50.0, but the expected output is 50.0. However, the developer notices that if the method is changed to return int, the output becomes 50.0 as well. Which statement about implicit casting is true?
⚠ Common exam trap
Oracle often tests the misconception that implicit casting can happen in both directions (widening and narrowing) or that the return type determines the cast direction; the trap here is that candidates may think the `double` result is cast to `int` when the return type changes, but in fact the implicit cast occurs on the argument, not the result.
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
✓
The int argument is implicitly cast to double.
When a method expecting a `double` parameter is called with an `int` argument, Java performs implicit widening primitive conversion (casting) from `int` to `double`. This is safe because `double` can represent all `int` values without loss of precision. The `int` value 1000 is automatically converted to `1000.0` before being used in the calculation.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The double result is implicitly cast to int.
Why it's wrong here
Narrowing would require explicit cast.
- ✓
The int argument is implicitly cast to double.
Why this is correct
Correct widening conversion.
- ✗
The code fails to compile because of type mismatch.
Why it's wrong here
Compiles fine.
- ✗
The multiplication result is automatically rounded.
Why it's wrong here
Not automatic rounding.
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 →
Last reviewed: Jun 30, 2026
This 1Z0-811 practice question is part of Courseiva's free Oracle 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 1Z0-811 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.