During an interview, I received the questions to estimate the market of strollers in the US.
I structured as follows:
1. Number of babies born every year as 300M inhabitants / 80 years lifespan x 1% growth = 3,8M
2. On average 2 children so 50% are first child and 50% are second, third... child
3. I assumed that 80% of first children receive a new stroller while only 10% of second, third children receive a new stroller (90% inherit the stroller from the previous child) resulting in 1,7M strollers a year
4. Average price of 200$ so total market of 340M$
Does this sound like a good approach to you as unfortunately I didn't receive an offer to come back and I wanted to know if it might have had to do with my solution to the case.