mediumMultiple ChoiceObjective-mapped
PL-900 Practice Question: A company uses Power BI to monitor manufacturing…
A company uses Power BI to monitor manufacturing efficiency. The dataset includes a column 'RunTime' (in minutes) and 'DownTime' (in minutes). A user wants to calculate 'Availability' as (RunTime / (RunTime + DownTime)) * 100. Which DAX measure should be used?
⚠ Common exam trap
It's easy for candidates to confuse aggregate-level calculations (using SUM) with row-level calculations (using SUMX or AVERAGE), and they may forget to multiply by 100 when the requirement explicitly asks for a percentage value.
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
✓
Availability = DIVIDE(SUM([RunTime]), SUM([RunTime])+SUM([DownTime])) * 100
It uses the DIVIDE function to safely handle division by zero, and multiplies by 100 to express the result as a percentage. The formula sums RunTime and DownTime across all rows, then computes Availability = (Total RunTime / (Total RunTime + Total DownTime)) * 100, which matches the user's requirement exactly.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Availability = DIVIDE(SUM([RunTime]), SUM([RunTime])+SUM([DownTime])) * 100
Why this is correct
Correctly calculates percentage.
- ✗
Availability = DIVIDE(SUM([RunTime]), SUM([RunTime])+SUM([DownTime]))
Why it's wrong here
This returns a decimal, not a percentage.
- ✗
Availability = AVERAGE(Table[RunTime]) / (AVERAGE(Table[RunTime])+AVERAGE(Table[DownTime])) * 100
Why it's wrong here
This averages run time per row, not total availability.
- ✗
Availability = SUMX(Table, [RunTime]/([RunTime]+[DownTime])) * 100
Why it's wrong here
SUMX is used for row-by-row evaluation but may not aggregate correctly without context.
Go deeper
Related to this question
About these practice questions
One of 904 original PL-900 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 by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PL-900 practice question is part of Courseiva's free Microsoft 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 PL-900 exam.