UiPath-ADAv1 Studio Interface and Variables Practice Question
A developer is working in UiPath Studio and needs to store a collection of invoice amounts that will be processed in a loop. The collection should be created empty and then populated dynamically during runtime. Which variable type and initialisation should be used?
⚠ Common exam trap
The trap here is choosing a Dictionary or DataTable because they sound more 'advanced', but the scenario explicitly calls for a simple ordered collection of amounts with no key or table requirement.
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
✓
System.Collections.Generic.List(Of Double) with default value new List(Of Double)
A strongly typed List(Of Double) initialized with new List(Of Double) is the correct way to create an empty, dynamically growable collection of numeric invoice amounts. It allows adding items at runtime and works seamlessly with For Each loops. Other types either impose unnecessary structure or lose numeric precision.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
System.Collections.Generic.List(Of Double) with default value new List(Of Double)
Why this is correct
This type represents a strongly typed list of Double values. Initializing with new List(Of Double) creates an empty list ready to receive invoice amounts via Add. This is the most appropriate choice because it enforces numeric type safety and supports dynamic resizing. It integrates well with For Each loops and collection activities in UiPath.
- ✗
System.Collections.Generic.Dictionary(Of String, Double) with default value new Dictionary(Of String, Double)
Why it's wrong here
A Dictionary maps keys to values and is ideal when you need to look up amounts by invoice number. However, the scenario only requires storing a collection of amounts for sequential processing, not key-based retrieval. Using a Dictionary adds unnecessary complexity and does not match the simple list requirement.
- ✗
System.Data.DataTable with default value new DataTable
Why it's wrong here
A DataTable is designed for tabular data with rows and columns, often used with database or Excel activities. While it can store invoice amounts, it is overkill for a simple collection and requires defining columns and rows. The scenario does not mention tabular structure or data source integration.
- ✗
System.String with default value "" and append each amount as text
Why it's wrong here
Storing amounts in a String loses numeric type information and makes arithmetic or comparison operations cumbersome. You would need to parse the string back to numbers, introducing potential errors. This approach is not suitable for a collection of numeric values that will be processed in a loop.
About these practice questions
One of 285 original UiPath-ADAv1 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official UiPath exam blueprint
This UiPath-ADAv1 practice question is part of Courseiva's free UiPath 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 UiPath-ADAv1 exam.