Estimate the number of Cats in the USA?

We will use the below steps to solve the problem

1.Ask clarifying questions

2.Making certain assumptions

3.Defining the approach

4.Explaining the steps to solve

5.Solving the problem

Clarifying questions

Me- Are we talking about cats as pet animals or stray cats also?

Interviewer — Consider both

Me- Do we need to consider any specific colour of cats or all combined?

Interviewer- Consider all colors combined

Assumptions

Population of US = 300M

20% of household have pet’s animals

Approach

In this case we will use top-down approach as there is no limitation or bottleneck from supply side

Steps to solve

1.We will start with the population of USA

2.Assuming certain number of people per household we can find the total number of households

3.Assuming a certain percentage of household have pets we can get total number of households with pets

4.Find the households with cats as the pet animal

5.Assuming a certain no of cats per household we can find total number of household cats

6.Assume a certain number of stray cats

7.Thus, we can get total number of cats in USA

Solution

Population of USA = 300M

Considering Pets cats

Assuming 3 people per household we get

Total number of household = 300M/3 = 100M

Assuming 20% people have pet at home

Number of households with pets = 20% of 100M = 20M

Considering 50% pet animal to be cats we get

Number of households with cat as pets = 50% of 20M = 10M

Assuming 1.5 cats per household we get

Total number of household cats = 10M * 1.5 = 15M

Considering Stray cats

In this case we are considering a certain buffer for stray cats

Assuming stray cats to be 0.5M

Total number of cats in USA = 15M+0.5M = 15.5M

Thus, total number of Cats in USA = 15.5M