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Anonymous A

on Sep 12, 2018

Global

In the advanced Nutripremium case:

Assuming that a woman on average has 2 kids i.e. 18 months (1.5 years) in pregnancy. Assuming the average life span of a woman as 75 years. This gives me that on an average a woman will be pregant for 2% of those 75years.

How does that lead me to the conclusion that 2% of the women population will be pregnant at any given time.

Please suggest.

Thanks

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Anonymous

edited on Sep 12, 2018

Should be evident - maybe this will things clearer:

imagine that all women were born on the same day and die on the same day.
Now assume that a pregnancy will occur at a random point in their life (not between 20 and 40)
Then at any given time, it can be expected that 2% of women are currently pregnant
Now obviously not all women are born the same day - but obviously, pregnancies don't also occur at a random time in a woman's life. So the random time of birth "corrects" the non-random time of the pregnancy.

(As you should be able to guess by now, the 2% statement is only approximately true, as the age pyramid is not evenly distributed. But for case purposes it's close enough, I guess.)

5 comments

Vikas

on Sep 12, 2018

How does the correlation between 2% of time spent in pregnancy (18 months/75 yrs of avg life) and the population that will be pregnant work? How can one extrapolate the 2% avg time spent in pregnancy to 2% popn being pregnant.

Anonymous

on Sep 16, 2018

Hi Vikas, to me it seems completely obvoius: if every woman during her life is pregnant for 2% of that lifetime, then at any given time 2% of the female population should be pregnant. I actually don't know how to put it in simpler terms. Maybe it'll help you to do the actual math (like with formulas)?

Anonymous

on Sep 16, 2018

Maybe try the same thing with school: Imagine a population of 750 people. The age distrbution is identical, so you have 10 people in very yearly cohort. Now assume that people spend 10 years in school, which is 10/75=13.33% of their lives. So there should be at any point in time 10 age cohorts of 10 people in school = 100 people. So 100 / 750 = 13.33%... Get it?

Anonymous

on Sep 16, 2018

Obviously, this works for any size of population, if you assume that age distribution is spread equally among age cohorts.

Vikas

on Sep 17, 2018

i will try again. thank you for your time. i understand that it is a simple thing but i dont know what is that i have been missing that is reqrd to understand this. may be , i am finding it tough to correlate the time spent % to % of people. i appreciate yourhelp

Vlad

Coach

on Sep 12, 2018

McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School

Hi,

Here we also assume that all the population is spread equally among the age groups - it means that at any given moment we have the same amount of people of each age.

Best

Contact coach

1 comment

Vikas

on Sep 13, 2018

Thank you. Agreed. But again it is the % of time spent on pregnancy i.e. 2%. But the solution says 2% of women population is pregnant at any point in time. How the avg time spent in pregnancy i.e. is 2% is extrapolated to 2% of population being pregnant.