Report design best practices in Power BI - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Choosing the right chart type for data

You have sales data by region and product category. Which chart type best helps compare sales across categories within each region?

A A stacked bar chart showing sales by category stacked for each region

B A line chart showing sales trends over time for each category

C A pie chart showing total sales by region only

D A scatter plot showing sales versus profit for each product

💡 Hint

Think about comparing parts within groups clearly.

A stacked bar chart allows easy comparison of sales by category within each region, showing both total and part contributions.

❓ visualization

intermediate

Improving dashboard readability

You have a dashboard with many charts and tables crowded together. What is the best practice to improve readability?

A Use very small fonts to fit more data on screen

B Add as many colors as possible to attract attention

C Increase white space and group related visuals logically

D Place all charts in one single page without scrolling

💡 Hint

Think about how your eyes move and focus on information.

Increasing white space and grouping related visuals helps users scan and understand the dashboard easily without feeling overwhelmed.

❓ dax_lod_result

advanced

Calculating sales per customer segment

Given a sales table with CustomerSegment and SalesAmount columns, which DAX measure correctly calculates total sales for the 'Corporate' segment only?

Power BI

Measure options:

A Total Corporate Sales = CALCULATE(SUM(Sales[SalesAmount]), Sales[CustomerSegment] = "Corporate")

B Total Corporate Sales = SUMX(FILTER(Sales, Sales[CustomerSegment] = "Corporate"), Sales[SalesAmount])

C Total Corporate Sales = SUM(Sales[SalesAmount]) WHERE Sales[CustomerSegment] = "Corporate"

D Total Corporate Sales = CALCULATE(SUM(Sales[SalesAmount]), FILTER(Sales, Sales[CustomerSegment] = "Corporate"))

💡 Hint

CALCULATE with FILTER is the correct syntax for conditional aggregation.

Option D uses CALCULATE with FILTER correctly to sum sales only for 'Corporate' segment. Option A is also valid using a shorthand boolean filter argument. Option B works but is less efficient. Option C is invalid syntax.

❓ data_modeling

advanced

Optimizing data model relationships

You have two tables: Customers and Orders. Customers has CustomerID as unique key. Orders has CustomerID as foreign key. What is the best relationship type to model this in Power BI?

A Many-to-one relationship from Orders to Customers with bidirectional filter

B Many-to-many relationship between Customers and Orders with bidirectional filter

C One-to-one relationship between Customers and Orders with single direction filter

D One-to-many relationship from Customers to Orders with single direction filter

💡 Hint

Think about uniqueness and filter direction for lookup tables.

Customers is lookup table with unique CustomerID, Orders is fact table with many orders per customer. One-to-many from Customers to Orders with single direction filter is best practice for performance and clarity.

🎯 Scenario

expert

Designing an accessible report for colorblind users

You are designing a sales report dashboard. How do you ensure it is accessible for users with color vision deficiency?

A Use color palettes with high contrast and add patterns or labels to charts

B Use only red and green colors to highlight increases and decreases

C Avoid using any colors and rely only on text data

D Use pastel colors with low contrast for a soft look

💡 Hint

Consider how colorblind users perceive colors and how to convey information clearly.

High contrast colors combined with patterns or direct labels help colorblind users distinguish data easily. Avoid red-green combinations alone. Text alone reduces visual appeal and pastel colors may lack contrast.