# Interview Question: Estimate the market demand in gallons for skim milk consumed in the U.S. in a given year.

## Strategy and Approach to Answering a Problem Solving Interview Question

If you get asked a problem solving question in an interview, remember that they are **NOT** looking for the **RIGHT** answer. They are evaluating the approach you use to think out and solve the problem. A strong candidate demonstrates the following:

- Evaluates and understand the scope of the problem
- Communicates assumptions
- Demonstrates quantitative analytical skills
- Answers the question that has been asked. You’d be surprised how many candidates get lost in the analysis and solve for a different question than what was asked.

## How to answer this problem solving interview question

Note, the interviewer is looking for your thinking process in these type of questions. Using the strategy outlined above, we need to define the scope of the question. We could be looking at consumer or institutional consumption. For this answer, we make an assumption that we are only considering milk consumed by households, and not milk purchased by institutions such as schools or restaurants or milk used to make other products like cheese.

Next we need make some assumptions on estimates:

- The U.S. population is 300 million
- 3 people per household or 100 million households
- Households with children probably consume 2 or more gallons per milk per week, but other households probably consumer well under a gallon since few adults drink milk as a beverage and if they drink it in their coffee, many purchase coffee outside of the home.

Let’s assume that if we averaged these two types of households together, the typical household consumes 1 gallon of milk per week. With 100 million households, there would be 100 million gallons per week consumed nationwide. However, the question had a twist in it that asked about skim milk consumption. Since there are many different varieties of milk (i.e. whole, 2%, 1%, skim, lactose-free). We’ll make another assumption that 20% of the market is skim. 20% of 100 million gallons equals 20 million gallons of skim consumed in a week. Multiplying 20 million by 52 gives us just over 1 billion, 1.04 billion gallons of skim milk consumed during the year.

**Note:** For this problem solving job interview question, there is an actual logical answer, however the interviewer will want to evaluate your thinking process. In answering the interview question, the lead up to your answer will be just as important as the actual answer itself.

*For more problem solving, brain teasers, riddles, puzzles, logic job interview questions, please check our out Problem Solving Interview Section.*

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