Guess Estimate

Guesstimates are a lot of fun !!

Guess estimate has become an important part of almost all the interviews related to Business Analysts or Data Scientists. The reason behind it being there in these interviews is that it checks two things, the ability of an individual to break down a problem in smaller chunks(much like business case study) and whether the candidate is able to crunch some basic numbers and maintain consistency to arrive on an answer. You should go through some already asked guess estimate questions to get yourself familiar with the solution approach. Two important things to keep in mind before attempting these questions:-
1. You need to cover a lot of different cases. Guess estimate is not about arriving on a particular number which is in the head of the interviewee, but it’s about developing an approach
2. Take a sample size which is closer to reality. Don’t take numbers in millions just to make your calculation easy

Let’s jump on to some questions

1. How much is the annual income of a beggar in Bangalore(OYO – Second round interview)

You can assume anything and everything under the Sun, just to try to keep the assumptions close to reality and inform the interviewee about these assumptions(if any)
I always start with an equation, for this question the equation which I assumed was:-

Amount per day * Number of Calendar Days (365)

Assumption 1- A beggar begs all day of the year

Now, I divided the complete day in 4 parts
6 am to 10 am – High income
10 am to 4 pm – Low income
4 pm to 10 pm – High income
10 pm to 6 am  – No income Assumption 2 – The beggar will bet more money in slot 1 and 3
Assumption 3 – Beggar interacts with 500 people in each slot
Assumption 4 – The success ratio table

Slot	Success Rate	Number of people giving money
6 AM – 10 AM	0.03	45
10 AM – 4 PM	0.01	15
4 PM – 10 PM	0.05	75
10 PM – 6 AM	0.006	9
		144

Assumption 5 – Probability of amount, I have safely assumed that 30% people will give Rs.2, 20% will give Rs.5 and 50% will give Rs.1

Slot	Success Rate	Number of people giving money	Amount
6 AM – 10 AM	0.03	45	94.5
10 AM – 4 PM	0.01	15	31.5
4 PM – 10 PM	0.05	75	157.5
10 PM – 6 AM	0.006	9	18.9
		144	302.4

Now we have Rs.302.4 per day income.
Annual amount = 302.4*365 =  Rs. 110,376 It doesn’t matter if the amount is high or low, what matters is that you have an approach to solve the problem. Few more things which you can add here are:-
1. Divide the year into seasons
2. Divide year into weekend and weekdays
3. Public Holidays

After providing a basic solution, do mention more points which you could have added 🙂

2. How many cars are there in Bangalore ? (Myntra Case Study Round)

Let’s directly jump to the approach part

Assumption 1 – Population of Bangalore, 10,000,000. If you are talking about a metro city in India then assume something between 5 Million to 15 Million. In case it’s about a town, then assume something around 1-5 Million.

Assumption 2 – Each family has 4 members, so the number of families will be 2.5 Million. From here you have to go concrete with your numbers

Now divide the families into 4 groups and assume a percentage distribution of the population(as a family)

Income category	Percentage of Family
Lower Middle Class	50
Middle Class	30
Upper Middle Class	15
High Class	5

Now we can assume the number of vehicle for each category

Income category	Percentage of Family	Number of vehicles
Lower Middle Class	50	0
Middle Class	30	1
Upper Middle Class	15	2
High Class	5	5

Assumption = Middle class have only two-wheeler, upper middle class have one two-wheeler and one four wheeler, high class will have 4 four wheeler and 1 two wheeler. So we can now calculate number of two and four wheelers in the city

Income category	Percentage of Family	Number of vehicle	Two wheeler	Four wheeler
Lower Middle Class	50	0	0	0
Middle Class	30	1	750000	0
Upper Middle Class	15	2	375000	375000
High Class	5	5	125000	500000

You can add other parameters like:-
1. Number of cabs
2. Divide the whole population into 2 group, cab drivers and others. Assume that 10% are cab drivers and 40% of these cabs are only bought for rent purpose. This way you will have =(((2500000*10)/100)*40)/100. Here we have also assumed that there is only one cab driver in a family of 4. You will be good to go unless your assumptions are not intersecting and the calculation is clean