Area 1.3

Problem-Solving Strategies

Master systematic approaches to problem solving including top-down, bottom-up, and modular strategies. Learn root cause analysis techniques and apply the complete problem-solving cycle.

3
Approaches
6
Cycle Steps
~3hrs
Study Time

Learning Objectives

  • Understand top-down, bottom-up, and modularisation approaches to problem solving
  • Apply root cause analysis techniques including five whys, FMEA, and event tree analysis
  • Use the high-level problem solving cycle: define, gather, analyse, plan, implement, review
  • Judge the suitability of different problem-solving strategies for specific contexts
  • Select appropriate analytical techniques based on problem characteristics

Problem-Solving Approaches

Top-Down

Start with the big picture and break it down into smaller components

Process:

  1. Identify main goal
  2. Break into major components
  3. Subdivide each component
  4. Continue until actionable tasks

Advantages:

  • Clear overall vision
  • Good for planning
  • Ensures nothing major is missed

Disadvantages:

  • May miss important details
  • Can be inflexible
  • Assumes requirements are clear

Best For:

Well-defined problems, new projects, strategic planning

Bottom-Up

Start with detailed components and build up to the complete solution

Process:

  1. Identify available resources
  2. Build basic components
  3. Combine components
  4. Scale up to full solution

Advantages:

  • Uses existing assets
  • More flexible
  • Good for innovation

Disadvantages:

  • May lack coherent vision
  • Can be inefficient
  • Risk of scope creep

Best For:

Research projects, when reusing existing components, exploratory development

Modularisation

Divide problems into independent, interchangeable modules

Process:

  1. Identify natural boundaries
  2. Define clear interfaces
  3. Develop modules independently
  4. Integrate and test

Advantages:

  • Parallel development
  • Easier testing
  • Reusable components
  • Better maintenance

Disadvantages:

  • Initial overhead
  • Integration complexity
  • Interface dependencies

Best For:

Large projects, team development, systems requiring maintainability

Root Cause Analysis Techniques

Five Whys

Ask "why" five times to drill down to root causes

Example:

Problem: Website is slow → Why? → Database queries are slow → Why? → No indexes → Why? → Poor initial design → Why? → Insufficient planning → Why? → Tight deadline pressure

Benefits:

  • Simple and quick
  • No special training required
  • Gets to root cause

Limitations:

  • May not find all causes
  • Depends on knowledge
  • Can be subjective

FMEA (Failure Mode and Effects Analysis)

Systematic method to identify potential failures and their impacts

Example:

Analyse each component: What can fail? → What causes it? → What are the effects? → How likely? → How severe? → How detectable?

Benefits:

  • Comprehensive analysis
  • Prioritises risks
  • Preventive approach

Limitations:

  • Time-intensive
  • Requires expertise
  • Can be overwhelming

Event Tree Analysis

Forward-looking analysis of possible outcomes from an initial event

Example:

Server failure → Backup works? → Load balancer redirects? → Users experience downtime or seamless service

Benefits:

  • Visual representation
  • Shows probabilities
  • Good for safety analysis

Limitations:

  • Complex for many variables
  • Requires probability data
  • Can miss dependencies

High-Level Problem-Solving Cycle

1

Define

Clearly articulate the problem and success criteria

Key Tasks:

  • Problem statement
  • Success metrics
  • Constraints
  • Stakeholders
2

Gather

Collect relevant information and resources

Key Tasks:

  • Data collection
  • Research
  • Requirements
  • Resources
3

Analyse

Examine the information to understand the problem

Key Tasks:

  • Root cause analysis
  • Pattern identification
  • Impact assessment
  • Risk analysis
4

Plan

Develop a strategy and detailed plan of action

Key Tasks:

  • Solution options
  • Resource allocation
  • Timeline
  • Contingency plans
5

Implement

Execute the planned solution

Key Tasks:

  • Task execution
  • Monitoring progress
  • Adjustments
  • Communication
6

Review

Evaluate the results and learn from the experience

Key Tasks:

  • Outcome assessment
  • Lessons learned
  • Process improvement
  • Documentation

Learning Activities

Strategy Selection Workshop

Analysis
45 minutes

Given various problem scenarios, choose and justify the best problem-solving approach

Root Cause Investigation

Investigation
60 minutes

Use five whys, FMEA, and event tree analysis on a software failure scenario

Problem-Solving Cycle Practice

Practical
90 minutes

Apply the complete cycle to a real programming challenge