A Parivartana Consulting Pvt. Ltd. Initiative CRACKING THE CASE INTERVIEWS Workshop with Vijay Khairnar
A Parivartana Consulting Pvt. Ltd. Initiative
CRACKING THE CASE INTERVIEWS
Workshop with Vijay Khairnar
2
August 21Private & Confidential
Structure of the workshop
Session # Title Duration
1 Introduction, Solving Guestimates And Market Sizing Cases 90 mins
2 Growth Strategy / Revenue Enhancement Cases 60 mins
3 Profitability / Cost Reduction Cases 60 mins
4 Customer Satisfaction/ Loyalty 60 mins
What you’ll learn✓ How to crack all manner of case studies including: Market Sizing, Profitability etc.
✓ Multiple frameworks to help you structure your thinking in a case interview
✓ All the business and consulting terminology necessary in a case interview
✓ How a case interview is conducted through interactive case interview examples
✓ Tips to help when preparing for online case interviews
3
August 21Private & Confidential
Who am I?
• Strategy consulting professional with 11+ years of experience
• Expertise in Growth Strategy, Cost Reduction and Business
Transformation
• Cracked case interviews of Tier-1 (MBB), Tier-2 and boutique
consulting firms
• Conducted >100 case interviews across B-schools and lateral hires
• MBA from XLRI, Jamshedpur (2011)
Vijay Khairnar
4
August 21Private & Confidential
Session#1: Agenda
1 What is case interview?
2 Why do companies take case interview?
3 Typical flow of a case interview
4 Different parts & progression of a case interview
5 Types of case studies
6 Guestimates and market size estimation cases
5
August 21Private & Confidential
What is case interview?
• Solve a broad business problem that is analogues to a real-life concern of a
company
• E.g.,
• Should a Finnish mobile manufacturing company enter Indian market?
• How should airline price the flights on a particular route?
• In what ways can FMCG company improve the revenue of a particular brand?
• What should a steel manufacturer do to improve its profitability?
• In real-world, consultants will take months to solve these problems. You are expected
to solve in a 30-min or 1-hour case interview
Hence, APPROACH is far more important than the final solution!
6
August 21Private & Confidential
Why do companies take case interview?
Problem solving skills
Business acumen
Quantitative skills
Logical thinking
style
Clear & effective communication
Testing core
strategy skills –
all at once !
Companies following case
interview approach:
✓ Strategy consulting firms
✓ Leading tech firms
✓ Conglomerates for Corp Strategy/
General management roles
✓ Data and analytics firms
7
August 21Private & Confidential
Typical flow of a case interview
INTERVIEWER:
Presents background, problem
and objectives of the case
(understanding the case
background information)
YOU:
Synthesize major points of the
case and verify objectives
(Verifying objectives)
YOU:
Request time to structure your
thoughts into a framework
(Developing a structured
framework)
YOU:
Present the framework to the
interviewer
(Presentation &
communication)
YOU + INTERVIEWER
Interviewer reviews your
framework, suggests the area to
start with OR you’ll be expected
to suggest (Start the case)
YOU + INTERVIEWER
Gather assumptions to solve
the quantitative problem
(Quantitative skills)
YOU + INTERVIEWER
Solve qualitative questions on
business judgement/ intuition
(Logical thinking style)
YOU + INTERVIEWER
The interviewer will ask you to
summarize/ provide final
recommendations
(Delivering a conclusion)
YOU
Differentiate yourself with
additional insights/ ability to see
a larger picture
(Taking it forward)
8
August 21Private & Confidential
Different parts & progression of a case interview
• Listen to the problem statement carefully
• Note down the key information (about industry, company, customer, market, pain
points)
• Ask question if not clear
Understanding the case background information1
• Take a moment to consume the information provided
• Summarize the case background and objective to the interviewer
• Ask the interviewer if your understanding is correct or not
Verifying objectives2
9
August 21Private & Confidential
Different parts & progression of a case interview
• Analyze the problem statement and think about an approach/ framework to solve in a
structured manner
• You may leverage the standard frameworks like Ansoff matrix, BCG matrix, Porter’s
framework, 3C framework etc. (only if they are directly applicable)
Developing a structured framework3
• Share your thought process (or framework) with the interviewer before starting to solve
the case. Explain your rationale.
• Demonstrate your overall approach to solve all aspects of the problem at hand
• Ask the interviewer if your approach is correct and whether you are missing any
aspects
Present your framework/ structure/ approach 4
10
August 21Private & Confidential
Different parts & progression of a case interview
• Take 2-4 mins to build your solution/approach in line with the framework
• Narrate the solution/ approach to the interviewer
Solve the case5
• Share your assumptions and calculation methodology with the interviewer
• Ask the relevant questions and seek the required data
• It will be ideal if you speak your math out loud
• Think how best can you triangulate your result
Quantitative skills6
11
August 21Private & Confidential
Different parts & progression of a case interview
• For the qualitative parts of the case (e.g., competitive analysis, industry analysis,
customer response etc.), leverage your industry expertise and/or business acumen
• Out of the box thinking is always appreciated
Qualitative question solving (logical thinking)7
• Share your conclusion with rationale to the interviewer
• Many a times, this is followed by a subsequent twister – Do not outrightly negate your
solution. Rather, think how best can you further improve your solution given the
additional information
Delivering a conclusion8
12
August 21Private & Confidential
Types of cases
# TYPE SUB-TYPE
1 Guestimates Top-down, bottom-up, mixed
2 Market size estimation Top-down, bottom-up, mixed
3 Growth StrategyRevenue acceleration, business diversification, Acquisition,
market share improvement, market-entry strategy
4 Profitability Cost reduction, Pricing strategy
5 Customer satisfactionCustomer experience enhancement, Loyalty improvement, churn
reduction, Brand advocacy improvement, NPS improvement
6 MarketingGo-to-market strategy, Pricing strategy, Promotion strategy,
Marketing channel mix, Campaign effectiveness
7 Supply chain/ OperationsNetwork optimization, Logistics cost optimization, warehousing
and distribution, supplier rationalization
13
✓ There are no correct answers: The aim is to be logical
✓ Don’t tie yourself in knots: round-up/ down the numbers whenever
possible
✓ Write it down: Do not treat the piece of paper as a rough calculation
sheet
✓ Speak up: The time you speak for should always be greater than the
time you spend calculating
August 21Private & Confidential
Tips for solving case studies during the interview
14
1. GUESTIMATES
August 21Private & Confidential
15
August 21Private & Confidential
1. What are guestimate case studies?
Guesstimate questions in interviews ask the candidate to estimate a number based on very limited information (hence “guess”)
Top-downQuestions that involve starting with an entire
population (in other words, the “top” level) and
then breaking it down until you arrive at an answer
Bottom-upStart from the “bottom”—some low-level
statistic, such as Revenue per customer,
and build your way up to the answer
Example guesstimate questions:
•How many mattresses are sold in India every year?
•What is the monthly profit of your favorite restaurant?
•How many bottles of coca-cola are there in circulation in India now?
•How many weddings are performed in India per year?
•How many flights have a lay-over at Dubai Airport in year?
•What would be the revenue of a Lakme Hair Salon in South Delhi?
(Top-down)
(Bottom-up)
(Top-down)
(Top-down)
(Bottom-up)
(Bottom-up)
16
GUESSTIMATE CASE #1
Solving a case study
August 21Private & Confidential
Guestimate Case #1
August 21Private & Confidential
How many cups of tea is consumed in Mumbai per month?
Step 1: Clarify the question
Step 2: Inform the interviewer about your thought process (Assumption and approach)
Approach :
• Break down the monthly consumption into weekly consumption;
• Divide the population by types of tea-drinking pattern (Habitual, Regular, Occasional and
none);
• Determine the per week consumption for different types of tea-drinkers
Key Assumptions to start with:
• Same consumption on all days of the week;
• Mumbai population is ~2 Cr
Guestimate Case #1
August 21Private & Confidential
How many cups of tea is consumed in Mumbai per month?
Step 3: Build on the approach
Eliminating children, who are ~10% of
the population
Habitual drinkers (25%)
~2 cups per day i.e., 14
cups per week
Regular drinker (40%)
1 cup per day i.e., 7
cups per week
Occasional drinkers
(25%)
2 cups per week
Non-Tea drinker
(10%)
0 cups per week
Mumbai Population : 2Cr
Addressable population: 1.8Cr
Tea-cups
consumed per
week
1.8*25%*14
= 0.45*14
= 6.3 Cr
1.8*40%*7
= 0.72*7
= 5.04 Cr
1.8*25%*2
= 0.45*2
= 0.9 Cr
Total tea-cups
consumed per
month
[6.3+5.04+0.9] * 4 = 12.24 * 4 = 48.96Cr = ~49 Cr
19
GUESSTIMATE CASE #2
Solving a case study
August 21Private & Confidential
Guestimate Case #2
August 21Private & Confidential
Estimate the profit of your favorite restaurant in your city
Step 1: Clarify the question
Step 2: Inform the interviewer about your thought process (Assumption and approach)
Clarify the context and scope
• Tell a few facts about your favorite restaurant to build the scope
• Shivsagar Restaurant : family dining place in the suburb
• Operates 4 hours in the morning and 4 hours in the evening
• Serves veg food and non-alcoholic beverages
• Considering only dine-in side of the business (Ask the interviewer if he/she is ok with this assumption)
Approach :
• Determine monthly revenue based on per customer invoice amount and capacity utilization
• Determine monthly cost : fixed cost and variable cost
• Estimate operating profit before tax, depreciation and amortization (Ask the interviewer if he/she is ok
with this understanding)
Guestimate Case #2
August 21Private & Confidential
Estimate the profit of your favorite restaurant in your city
Step 3: Calculate the revenue
Revenue per week = number of tables * number of customers per table per week *
revenue per customer
Number of tables: 20 (you know it! It’s your favorite restaurant)
Number of customers per table per week:
Revenue per customer : INR 2,000 (assumption)
Revenue per week = 20* (18+20)* 2000 = INR15,20,000
Revenue per month = INR 60,80,000
Weekdays (Monday lunch to Friday lunch) i.e. 9
slots of 4 hours each
• Utilization : 50%
• Hours per customer : 1 hour
• Total customers per table = 9*4*50% / 1= 18
Weekend (Friday dinner to Sunday dinner) i.e. 5
slots of 4 hours each
• Utilization : 100%
• Hours per customer : 1 hour
• Total customers per table = 5*4*100% / 1 = 20
Guestimate Case #2
August 21Private & Confidential
Estimate the profit of your favorite restaurant in your city
Step 4: Calculate the cost
Total cost per month = Fixed cost + (Variable cost per customer * total customers per month)
Fixed cost = Rent + Utilities + Salary of staff + License & Insurance
Staff break-up = Chefs + Waiters + Cleaners + Admin/cashier
= (3*75,000) + (8*20,000) + (3*8,000) + (1*15,000) = INR 4,24,000
Fixed cost = 300,000 + 30,000 + 4,24,000 + 11,000 = INR 7,65,000
Variable cost = Raw material
Assumption : Food raw material is ~50% of the price of the dish
Total variable cost per month
= (Revenue per customer * 50%) * number of customers served per month
= (2000 * 50%) * ((18+20)*20*4)
= 1000 * 3040 = INR 30,40,000
Total cost per month = INR 38,05,000
Guestimate Case #2
August 21Private & Confidential
Estimate the profit of your favorite restaurant in your city
Step 4: Calculate the Profit
Operating profit per month = Revenue – (Fixed Cost + Variable Cost)
= 60,80,000 – 38,05,000
= INR 22,75,000
Annual operating profit = INR 2.73 Cr
Step 5: Share further information around how will you calculate the net profit
• Estimate the capital expenditure and potential debt
• Determine the interest, depreciation and taxes
• Estimate the net profit
• If the capex is funded through own money, we can calculate ROI and break-even period
24
2. MARKET SIZING CASES
August 21Private & Confidential
25
August 21Private & Confidential
1. What are market sizing studies?
Estimate the market size (e.g: “annual sales”) of a certain product, often using limited information.
B2C Focuses on estimating the number of
customers/ users and then estimating the
consumption per user
B2BInvolves identifying the end-use sectors
and relevant markets followed by
estimating the demand per sector and
market
Example guesstimate questions:
• What is the market size of pressure cookers in India?
• What is your estimate of electric 2W market in your city?
• What is the market size of steel rods in India?
• How big is the market for online gaming apps in India?
• What could be the market size for organized tea chains in India?
26
MARKET SIZING CASE #1
Solving a case study
August 21Private & Confidential
Market sizing case #1 27
August 21Private & Confidential
What is the market size for online eye-glasses market in India?
Step 1: Clarify the question
Step 2: Inform the interviewer about your thought process (Assumption and approach)
Clarify the context, assumptions and scope
• Eye-glasses for this case are only with powered lenses
• Sunglasses, fashion accessories are not considered in the scope (Ask the interviewer if
he/she is ok with this assumption)
Approach :
• Determine the population which would use eye-glasses
• Estimate the consumption per year per customer to determine the total units sold
• Estimate annual sales by multiplying the average price of the eye-glasses
• Estimate the share of customers adopting online purchases in eye-glasses category
Market sizing case #1 28
August 21Private & Confidential
What is the market size for online eye-glasses market in India?
Step 3: Start solving the case Total Population : 1.4 Bn
Age 0-20 (25%) Age 21-60 (50%) Age 60+ (25%)
Total market size = INR 1,785 Cr
Population (Mn) 350 700 350
% people wearing eye-glasses 10% 50% 100%
# people wearing eye-glasses (Mn) 35 350 350
Eye-glasses replenishment cycle 2 years 4 years 5 years
% of online adopters 1% 5% 0%
Avg price of eye-glasses (INR) 2000 4000 5000
Online annual sales of eye-glasses
(INR Mn)
=(35/2)*1%*2000 =
350
=(350/4)*5%*4000
=17,500
=(350/5)*0%*5000
= 0
Online Eye-glasses market size (INR Cr) 35 1,750 0
Market sizing case #1 29
August 21Private & Confidential
What is the market size for online eye-glasses market in India?
Step 4: Share further insights to demonstrate your ability to see a larger picture
This market size is expected to grow as the penetration of ecommerce in eye-glasses
segment increases. Factors fueling this penetration –
• Smartphone usage
• Penetration of ecommerce companies in Tier 3 cities
• AR/ VR enablement in smartphones
Ask the interviewer if he/she wants you to calculate sunglasses market as well.
30
MARKET SIZING CASE #2
Solving a case study
August 21Private & Confidential
Market sizing case #2 31
August 21Private & Confidential
Our client is a leading lithium-ion battery manufacturer in Japan. They
want to enter Indian market and have hired you to estimate the market
size in India.
Step 1: Clarify the problem statement and ask any additional questions you may have
Step 2: Inform the interviewer about your thought process (Assumption and approach)
Approach :
• Estimate the # batteries required by auto manufacturers – 2W, 4W, commercial vehicles
• Estimate the demand in after-sales market
• Lithium-ion battery has applications in multiple end use sectors. What are the end-use
sectors the client is operating in? – Automotive
• Do they want to stick to the same sectors in Indian market? - Yes
Note: In B2B market sizing case, you may need multiple datapoints which you can not guess like
population of India. Ask for these datapoints at the relevant stage in the calculation
Market sizing case #2 32
August 21Private & Confidential
Step 3: Start solving the case
Lithium-ion battery market size for automotive sector in India
Total Battery consumption
New vehicles Old vehicles
• Data required:
• Annual production of 4W, 2W and CV
• Cost of a battery per type of vehicle
• # of batteries consumed will be same as the
production
• Data required:
• Number of 4W, 2W and CV on the road
• After-market price of the battery per type of
vehicle
• Assumptions/ Data required:
• Avg life of a battery for 4W, 2W and CV
• Battery consumption per year per type of vehicle =
Number of vehicles on road / avg lifespan of the battery
Note: Interviewer may handover the data to you in the form of tables/ graphs as case appendix OR
can provide you the datapoints verbally.
Market sizing case #2 33
August 21Private & Confidential
Lithium-ion battery market size for automotive sector in India
Appendix A :
Automobile
production trends
Type 4W 2W CV
Avg wholesale price 4,700 2,600 6,500
Avg retail price 6,000 3,500 8,000
Avg lifespan 4 years 5 years 3 years
Appendix B :
Battery details
Market sizing case #2 34
August 21Private & Confidential
Lithium-ion battery market size for automotive sector in India
Key Assumptions to validate with interviewer
• For simplicity, we are assuming that the production is equal to sales
• Average lifespan of the vehicle is 10 years. Thus, total vehicles on the road will be twice the
cumulative sale of last 5 years
• New car batteries are purchased by auto manufacturer. Hence, they will buy it at wholesale price
• Old car batteries are purchased by individuals. Hence, they will buy it at a retail price
• Other types of vehicles are not considered in the scope at this moment
Homework : Please calculate the market size and verify with your friend
Market sizing case #235
August 21Private & Confidential
Lithium-ion battery market size for automotive sector in India
Step 4: Share further insights to demonstrate your ability to see a larger picture
This market size can be divided into addressable vs non-addressable market for the Client
based on following factors –
1. Eliminating the demand of auto manufacturers who have in-house battery manufacturing
2. Any specific requirements from the vehicle manufacturers restricting the usage of third-
party batteries in after-sales
3. Battery distribution network in the after-sales
36
Q&A
August 21Private & Confidential
36
37
Growth Strategy/ Revenue enhancement cases
August 21Private & Confidential
Next session