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213 questions collected

Blackrock has 213 published OA questions on OAHelper. Most reported topics: SQL, Logical Reasoning, Math, Attention to Detail, Oracle.

Recurring Topics

  • SQL
  • Logical Reasoning
  • Math
  • Attention to Detail
  • Oracle
  • Database
  • Flowchart
  • Data Interpretation
  • Data Structures
  • Python
  • Aptitude
  • Binary Tree
  • Percentages
  • Binary Search Tree
  • Tree Traversal
  • Algorithms
  • Recursion
  • Arithmetic
  • Algorithm Tracing
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  • Averages
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  • Word Problems
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  • Complementary Counting
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  • Time Speed Distance
  • Logical Deduction
  • Statistics
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  • ORDER BY
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HotAug 24, 2026

blackrockOA Insights - Online Assessment Pattern & Topics

213 questions collected

What to Expect

Blackrock has 213 published OA questions on OAHelper. Most reported topics: SQL, Logical Reasoning, Math, Attention to Detail, Oracle.

Topics

Questions

213

Selenium Java: Failure Page Source Capture

medium

Word-Score Flowchart: The Inner Loop Exit Test

medium

Word-Score Flowchart: Scoring a Consonant

medium

Word-Score Flowchart: The Outer Loop Counter

medium

The Word That Is Not an Oracle SET Operator

medium

What a UNION of EMPLOYEES and JOB_HISTORY Returns

medium

Root After Deleting and Reinserting 45 in the AVL Tree

hard

Output of operate on the Array-Encoded Tree

medium

In-order Traversal of the Twelve-Key BST

medium

Post-order Traversal of the Twelve-Key BST

medium

Pre-order Traversal of the Twelve-Key BST

medium

Change in the Number of Left Children After Mirroring

medium

Root of the Tree After the Mirror Routine

medium

Flowchart Word Scorer: What Goes in Cell 4

medium

Depth of the Mirrored Binary Tree

medium

Spotting Wrong Customer IDs Against Contact Numbers

medium

Two-Squares Flowchart: Splitting the Number

medium

Flowchart Word Scorer: What Goes in Cell 3

medium

Confirming Correct Contact Numbers for Five Customers

medium

Two-Squares Flowchart: Marking the First Representation

medium

Spotting Wrong Contact Numbers for Five Customers

medium

Matching Drill and Cutter Part Numbers to Their Names

medium

Prime-Sum Flowchart: Advancing the Candidate

medium

Matching Punch and Reamer Parts to Their Part Numbers

medium

Flowchart Word Scorer: What Goes in Cell 1

medium

Seven in a Row: Which Pair Sits Together

medium

Prime-Sum Flowchart: Advancing the Trial Divisor

medium

Drill and Cutter Codes: Matching Numbers to Names

medium

Maximum Average Annual Growth from 1996 to 2000

medium

Prime-Sum Flowchart: Initialising the Trial Divisor

medium

Highest Five-Year Average Paper Production

medium

Largest Single-Year Growth in Paper Production

medium

Prime-Sum Flowchart: the Loop Termination Test

medium

Phone Numbers and Customer IDs: The Wrong Pairings

medium

Missing Term in the Series 1, 3, 2, 8, 5, __, 26

medium

Which Word Comes Next

medium

Filling the CY Cell of a 3x3 Equal-Sum Grid

medium

Multi-Linked Structure Used for Storing Images

medium

Punches and Reamers: Which Part Numbers Are Right

medium

Coding CRYSTAL When ABSOLUTE Is 1CT4M5V2

medium

Coding PALLAVI in the DEEPALI Language

medium

Contrapositive of John's Work-and-Pay Conditional

medium

Internal Storage Structure of a Relational Database

medium

Value of the Symbolic Expression

medium

Fastest Average Annual Growth Over Five Years

medium

Juice-to-Pulp Ratio After a 300 g Apple Dries to 200 g

medium

Minimum and Maximum Nodes Traversed in a BST Search

medium

When Five Visitors at Intervals 1 to 5 Next Coincide

medium

What G Wanted to Become

hard

Finding X When Ten More Men Save Twenty Days

medium

New Root After Inserting 10 into the BST

medium

Seven in a Row: Who Sits Side by Side

medium

Probability of Rolling a Sum of Nine with Two Dice

medium

Income Tax Increase and Implicit Assumptions

medium

Function That Prints the In-Order Traversal

medium

Probability a Drawn Card Is a Spade or a Queen

medium

Largest Year-on-Year Jump in Paper Output

medium

Litres of 10% Solution Added to Reach 12% Salt

medium

Function That Prints the Post-Order Traversal

medium

Stoppage Minutes per Hour at 64 and 55 kmph

medium

Data Sufficiency: Profit or Loss on Apples

medium

AVL Root After Deleting and Re-inserting 45

hard

Total Principal from Matching Simple and Compound Interest

medium

Function That Prints the Pre-Order Traversal

medium

Sugar Expenditure After a 20% Price Rise and 25% Cut

medium

Mirroring a BST: The Root Afterwards

medium

Completing the preOrder Scanner for the Prefix Form

hard

Ratio Expression from a/b = 2/3 and c/b = 3/2

medium

Syllogism: All Jokers Are Kings, Some Kings Are Red

medium

Mirroring a BST: Change in Left-Child Count

medium

Postfix Form of a Parenthesised Expression

medium

Cost of R Pens and R Markers

medium

Return Value of operate(root, 4) on a Seven-Node Tree

medium

Prefix Form of a Parenthesised Expression

medium

Data Sufficiency: Whose Savings Are the Highest

medium

What the Recursive operate() Function Does

medium

Interleaved Squares Series: 1, 3, 2, 8, 5, ?, 26

medium

BST In-order Traversal of a Twelve-Key Insert

medium

Completing a Nine-Number Equal-Sum Grid

medium

BST Post-order Traversal of a Twelve-Key Insert

medium

What the Three-Table SELECT Represents

medium

Which Symbol-Substituted Inequality Is False

medium

BST Pre-order Traversal of a Twelve-Key Insert

medium

UNION ALL of Two Single-Row Queries

medium

Return Value of CONNECT_BY_ISCYCLE

medium

Two Typists, One Three Times Faster

medium

Data Sufficiency: Counting the Girls in a Class

medium

Which Statement Follows From a Compound Conditional

medium

Unique Combinations of Two Columns

easy

Ram's Maximum Average Weekly Wage

hard

Juice to Pulp in a Dried Apple

medium

Engine Power: Compensating a Bore Increase

medium

Employees with More Than Ten Years of Service

medium

Five Visitors on Different Cycles Meet Again

medium

Four Friends, Ten Hotels, At Least One Shared

medium

Creating a View over Column Aliases

medium

Ten Extra Men Finish Twenty Days Sooner

medium

Guaranteed Divisor of Three Consecutive Even Numbers

medium

Column Count of a Cross Join

medium

Rolling a Total of Nine With Two Dice

easy

Vowels Together in MULTIPLE

medium

Nested ROUND, TRUNC and MOD on 1600

medium

Spade or Queen From a Standard Deck

easy

Men and Boys Painting a Wall

medium

Character Function That Returns a Number

medium

When Two Simple Interests Coincide

medium

Group Function for a Department Sales Total

easy

Diluting a 20% Salt Solution Down to 12%

medium

Eight Friends in a Circle: Which Statement Holds

hard

Minutes a Train Stops per Hour

medium

Rounding a Date to the Nearest Year

medium

Six-Month Sales Graph: Best Average Monthly Growth

hard

Split Savings Across Simple and Compound Bonds

medium

Six-Month Sales Graph: Minimum Total Revenue

medium

Sugar Bill After a Price Rise and a Consumption Cut

medium

How NVL2 Differs from NVL

medium

Six-Month Sales Graph: Highest Average Revenue

medium

CLOB Result Exceeding the Maximum Length

medium

Trains and Platform: Pick the Valid Deduction

medium

Arithmetic Operator for a Product

easy

Grocer's Apple Profit Expression

medium

Part Catalogue: Matching the Mild Steel Washer

medium

Correct Definition of a View

easy

Milkman's Extra Water and Extra Price

medium

Part Catalogue: Spotting the Ball-Bearing Match

medium

Valid Representation of DDL

easy

Ratio Algebra: Squares of a and c Over b

medium

Annual Compensation with a Monthly Bonus

medium

Marble Game Flowchart: The Termination Test

medium

Which Is Not a Valid Character Set

easy

Address Register Lookup: Barbara Richart

easy

Marble Game Flowchart: Keeping the Score Non-Negative

medium

Address Register Lookup: Lucille Gordon

easy

Marble Game Flowchart: Scoring the Blue Pair

medium

Address Register Lookup: Jessica Pope

easy

Default Precision of INTERVAL YEAR TO MONTH

medium

Marble Game Flowchart: The First Decision

medium

Part Catalogue Audit: Feed Arm Lever Cam Roll Code

easy

Median Flowchart: Choosing the Median Formula in Cell 5

medium

Part Catalogue Lookup: Spotter Head Clamp

easy

Median Flowchart: The Pass-End Test in Cell 4

medium

Part Catalogue Audit: Spotter Plungers Code

easy

Median Flowchart: The Comparison in Cell 2

medium

Which SET Operator Does Not Exist

easy

Pole in the River: Deducing Its Length from the Rise

medium

Recovering a View's Defining Query

medium

The Parts of a Python List Comprehension

easy

UNION Across EMPLOYEES and JOB_HISTORY

medium

Customer Directory: The Only Correct Pairing

medium

Sum-of-Two-Squares Flowchart: Cell 5

medium

Customer Directory: Both Pairings Wrong

medium

Sum-of-Two-Squares Flowchart: Cell 4

medium

Customer Directory: Isolating the Wholly Incorrect Pairings

medium

Sum-of-Two-Squares Flowchart: Cell 2

hard

Printing Three Unpacked Values in Python 2

medium

Sum-of-Two-Squares Flowchart: Cell 1

medium

List Comprehension Producing [5, 5, 8] from a Matrix

medium

Implicit Assumptions Behind a Productivity Bonus

medium

Coded Operations: Evaluating F(F(E12 A E16) C F(50 B 5 C 5))

medium

Converting a List of Months to a Set

medium

Seven-Digit Numbers from a Digit Set Containing Zero

medium

Six People on a Line: Who Are Neighbours

medium

Data Sufficiency: The Class Average in Mathematics

medium

Three-Product Sales Chart: The Peak Month

medium

Diamonds, Thieves and Angels: What Kathy Keeps

medium

Average Speed over Two Legs in Ratio 2 : 3

medium

Data Sufficiency: Is x - y Positive

medium

Probability of Centuries in Four Specified Matches

medium

Loss in Value When a Diamond Breaks in Three

medium

Reaping the Field with More Men and Longer Days

medium

Twenty Percent Shorter, But How Much Taller

medium

Part Catalogue: Which Spring Code Matches Its Description

medium

Least Digit Making 451?603 Divisible by 9

easy

Games, Sports and Gambles: Which Conclusion Always Follows

medium

Doubling the Selling Price Quadruples the Profit

medium

Listing Departments Chronologically by Formation Date

medium

Classifying CREATE, SELECT, MERGE, RENAME, DROP and DELETE

medium

Which Employee Name Matches LIKE 'jack%'

medium

Clauses Allowed in the SELECT That Defines a View

medium

Result of ABS(+45) + ABS(-15) From DUAL

easy

Rows Returned by sal > ANY Intersected with sal < ALL

medium

Selecting ROWNUM From DUAL Filtered on ROWNUM

medium

Ensuring salary * Hike_percent Always Displays a Value

medium

Single Row Functions Versus Multiple Row Functions

medium

Which Statement About a Database Table Is True

medium

The Relational Principle Behind SELECT Search Criteria

medium

Which SQL Category the INSERT Statement Belongs To

easy

DECODE Compared Against a NULL Search Value

medium

Which Statement About the Set Operators Is True

medium

Function That Manipulates Character, Number or Date Columns

medium

CASE Expression Substituting 99 for a NULL Commission

medium

Recovering the Base Query of a Forgotten View

medium

Output of Sub.method Chaining Back to Super.method

medium

Valid Data Types for a Dictionary Key in Python

medium

Setting Trace Hooks to Monitor Functions in a Program

medium

Which Empty Class Definitions Run Without Error

medium

Comparing Two Sets After update With Existing Members

medium

Opening a Text File for Reading in Python

easy

Joining a Path List with '/'.join

easy

Calling str.partition With No Argument

medium

Centring a String to Width 24 with Asterisks

medium

Result of s[:1] + s[1:] for Any String

easy

Coding Language: RAINDROP Written as TCKPBPMN

medium

Build the List [3, 2, 1, 0, 1, 4] with append

medium

Median Flowchart: Recording That a Swap Happened

medium

Median Flowchart: Initialisation Before the Sort Loop

medium

Sprinter Speed Ratio Before and After Coaching

medium

Few-Shot Prompting: What Drives the Improvement

medium

Primary Benefit of k-Fold Cross Validation

medium

Embeddings Represent Text As

easy

Effect of Low Sampling Temperature

medium

Minimum Height

medium

Airport Baggage Handling System

easy
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