If I take population, segment by age group (say there are 10 M people in the 20-40 years category), can I find the # of couples in this age group by just thinking of it as 10 M people so that's 5M "pairs", I'll assume 30% are single and remaining 70% are couples..(so it's 70% x 5M pairs). Or is there another way to do this?
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Estimating # of couples
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Top answer
Deleted user
on Jun 29, 2021
Your approach seems to make sense for that particular age group.
But this questions seems a bit too simple for an actual interview case. If I was an interviewer I would probably ask some follow up question. E.g.
- What ways do you see to verify the 70%? What data points would you look at?
- What other way could you think of to estimate the number?
Might be an interesting exercise to further refine your consulting skills ;)
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Ian
on Jun 29, 2021
Coach
Top US BCG / MBB Coach - 5,000 sessions |Tech, Platinion, Big 4 | 9/9 personal interviews passed | 95% candidate success
Hi there,
That's right. You've actually overcomplicated a bit and can really just say "I think about 70% of that group are couples", then divide by two. It's a more logical/linear way of thinking!
Don't forget, uuse your own knowledge/experiences as a reference point when doing this. "I'll assume" is a weak statement in market sizing.
Antonello
on Jun 29, 2021
Coach
McKinsey | NASA | top 10 FT MBA professor for consulting interviews | 6+ years of coaching
Hi, if you are only interested in this age group it makes total sense
Best,
Antonello
Anonymous B
on Jun 29, 2021
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