Product Management interview question [Guesstimate]: Estimate the number of televisions in Delhi.

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This was asked to me in one of my interviews so this is the kind of question one can expect in Product Management interviews. I’m sharing my thought process on how to solve questions like these in the interviews.

I have a few clarifying questions before I start working on the solution -

1. Are we considering televisions in a broader term like tv screens in cars, monitors, projector displays, and others? — I’m assuming television here means a traditional television that we grew up watching. Sounds good? Yes.
2. I’m just considering the television used at homes; not considering the television in shops, hotels, hospitals, restaurants or any commercial establishment. Is that alright? — Sounds good
3. I’m considering working television, not the ones in junkyards, garbage, or someone’s storeroom collecting dust for decades. Sounds about right.
4. When we say Delhi I’m considering Delhi NCR — Sounds fine.

Okay with that I’ll start working on it, and will clarify if any questions come up. I’ll take a top down approach by taking the population of Delhi, making cohorts on certain demographics, and then coming up with an approximate number.

So the total population of Delhi NCR is around 4 crores.

I’ll break this number down into different cohorts based on income levels as owning electronic devices don’t come under the necessary survival items like food, water, and hence is a factor of income level and affordability.

So income based cohort segmentation should work best to get accurate approximations.

On an average a household in India consists of 4 crore people, so given that there are 4 crore people it is safe to assume that there are approximately 1 crores households — can be families, or can be a group of working bachelors living together.

Now, I’ll divide the 100% (1 crore households) population into 5 cohorts -

1. Below the poverty line — 15%
2. Above poverty line and middle class — 55%
3. Upper middle class and rich class — 25%
4. Ultra rich class — 5%

I have made this divide instead of the generally accepted lower class-middle class-upper class segmentation as TV is a cheaper commodity as compared to other luxuries (say car, house, iphones). One can easily buy a great TV in as little as 10K INR, so the upper middle class and rich class are fundamentally the same income bracket when it comes to buying television.

Now, these different income groups have different numbers of television needs and wants as per their affordability. Let’s explore -

1. Below the poverty line — fundamentally 0 needs and wants. Typically live without television — average 0 tv per household.
2. Above poverty line and middle class — Would have a tv in their hall where the family has dinner, watches movies on weekends — average 1 tv per household.
3. Upper middle class and rich class — Would typically have separate tvs in kids’ bedrooms or elder’s bedrooms — average 3 tv per household.
4. Ultra rich class — Delhi being the capital of India is home to some of the richest businessmen, diplomats and politicians in the county. These people typically have a couple of fully furnished servant quarters, guest rooms, etc — average 6 tv per household.

So, now calculating the total number of television in Delhi per household per income group -

1. Below the poverty line — 1 cr * 0.15 * 0 = 0
2. Above poverty line and middle class — 1 cr * 0.55 * 2 = 11000000
3. Upper middle class and rich class — 1 cr * 0.25 * 3 = 7500000
4. Ultra rich class — 1 cr * 0.05 * 6 = 3000000

So now adding 3000000 + 7500000 + 11000000 = 21500000 = 2 crore 15 lakhs

So the total number of television in Delhi NCR, which fits the criteria we discussed in the clarifying questions, is 2 crores 15 lakhs.