Grail Insights Interview Question: Estimate number of red cars i... | Glassdoor.co.in

## Interview Question

Analyst Interview New Delhi

# Estimate number of red cars in Delhi

1

Total population of Delhi - 2 crores
On an average every household has 0.75 cars
therefore total cars in Delhi 1.5 crores
Now out of the total colors sold suppose the combination of all cars is as follows
Black = 33%
White = 22%
Blue = 15%
Red = 10%
Therefore 10% of 1.5 crore will be 15 lakh cars in Delhi are Red

Pawan Jha on 25-Aug-2012
2

total population of Delhi= 2 crores (approx)
avg. family size is 4 members
therefore number of households in delhi will be around 50 lakhs ( 2 cr. divided by 4)

out of these 70% families will have the required annual income to afford a car, or will even require a car (estimated)

thus 70% of 50 lakhs is 35 lakh households

assumuing each household has atleast 1 car, we get 35 lakh cars on Delhi roads

Now the probability of a car being red is 1/10
that is, 1/(7 colors + black + white + Grey )

thus number of red cars in Delhi is 3500000x1/10

350000 cars