7 Quant Interview Questions (With Sample Answers)
In a quant interview, also called a quantitative interview, the interviewer asks you questions to see how good you are at analysing numbers. If you want to be a quantitative analyst or do something else that requires a lot of math skills, you might have to go through this kind of interview during your job search. If you think you might have a quantitative interview, it can be helpful to look over common questions and how they are asked before the interview. In this article, we explain seven quantitative interview questions and give examples of how to answer them.7 Quant Interview Questions (With Sample Answers)
Examples of how to answer questions about numbers
To help you get ready, here are some examples of good interview questions and how to answer them:
1. Can you tell me about your quantitative experience?
Interviewers might ask this to see if your past experiences have prepared you for the duties of the job they are offering. They might also be interested in your past and who you are. You can talk about your academic or professional background and how it might have prepared you for the job you’re applying for when you answer this question.
“I majored in math in college, and my senior thesis was about mathematical models of how populations grow. This was a great topic for me because it combined my love of math with my interest in social justice and global problems like overpopulation. After I graduated, I worked for a local state senator for six months as a campaign coordinator. I used what I knew about math to figure out how people were voting.
After the election, I decided that I wanted to work full-time in a quantitative field. Soon after that, I got a job as a quantitative analysis assistant at the ALANTIX Company. There, I learned how to use statistical analysis in a business setting to figure out how much financial risk there is. I’m excited to use the same skill as a quantitative analyst for your company and keep getting better by working with the great coworkers and mentors I’m sure to meet.”
2. How many degrees do the hour and minute hands on an analogue clock move apart at 3:15 a.m.?
This is a common quantitative interview question for technical and quantitative jobs because it shows how good a candidate is at both math and logic. Some people might picture a clock at 3:15 a.m. and think that the minute and hour hands are touching, so there are no degrees between them. Think about how each hand moves around the edge of the clock and then use what you know about angles to find the right answer.
Example: “A circle has a total of 360 degrees. At 3:15, the minute hand has gone exactly one quarter of the way around the clock. One quarter of 360 is 90, so the minute hand has moved exactly 90 degrees from a vertical position. This means that it’s pointing right at the 15-minute mark on the clock.
At 3:15, the hour hand of a clock is exactly a quarter of the way between three and four. This is because the time 3:15 means that exactly 15 minutes have gone by. If you divide 360 by 12, you get 30, which is how many degrees are in each hour. One quarter of 30 is 7.5, so when it’s 3:15, the hour hand on a clock is 97.5 degrees from being straight up. This means that the minute hand is 7.5 degrees ahead of the hour hand at 3:15 a.m. or 3:15 p.m.
3. Let’s say we are playing a game where we flip coins. I only have 19, and you have 20. Both of us flip all of our quarters at the same time. If more of your coins land with their heads up, you win. If we both have the same number of heads-up quarters or you have less, I win. What are the chances that you will win?
In quantitative interviews, interviewers often ask about probability, since many quantitative jobs require a basic understanding of probability. It can also be a good way to find out how good a candidate is at basic math and statistics. When answering this or any other probability question, it can help to think about which parts of the problem are most important to your answer. As you talk about your answer, you can point out the important parts to the interviewer.
Example: “In this situation, each of us has a 50/50 chance that the first 19 coins we flip will land on heads. This means that they pretty much cancel each other out, which makes them useless. There is a 50/50 chance that the last coin I flip will land heads up or tails up. This means that there is a 50% chance that it will land on its head. “I have a 50/50 chance of winning.”
4.Why did you choose to work in this field?
During an interview, this question can help potential employers find out more about your hobbies and work history. This could help them learn more about you as a person and decide if you would be a good fit for their business. Make a list of the things you like best about your job to answer this question. You could also share a personal story to help the interviewer get to know you better. Think about events, people you looked up to, or classes that made you who you are today.
“When I was a kid, I was always good at math and science, and I thought I would become a math teacher one day. I liked art too, but I always saw it as something I did for fun. When I was in middle school, an architect gave a talk at my school. I remember how amazing it was to hear them talk about how precise the job had to be and how much math was involved. It was the first time I had thought about how my good math skills and interest in art and design could work together.
5. Why do manhole covers have a round shape?
Interviewers might ask this question to see how good their candidates are at math and logic. There are more than one way to answer this question, so an employer may keep track of how many answers a candidate comes up with and when they decide to stop. It might help to fully explain one reason before moving on to the next when answering this question.
“The first thing that comes to mind about why a manhole cover is round is that it keeps it from falling into the hole. If the cover were a different shape, like a square, it might fall in because the distance from one corner to the next is less than the width of a square. When the cover is round, there is always the same amount of space between each side. This means that it can’t fall into the manhole no matter how you turn it.
The first reason is that it keeps people safe. Construction workers could be hurt if a manhole cover fell into a manhole. The fact that a manhole cover is round is also important to its function. The manhole covers are very heavy, which is the second reason. Because they are round, a single person can roll them. If the cover was different, this might not be possible.”
6. How many times do you have to fold a piece of paper before it is as tall as the Empire State Building?
This question could help the interviewer figure out how well a candidate can solve a puzzle with many steps and variables. You need to figure out how to estimate how high the Empire State Building is before you can answer this question. Next, you can talk about how to use math to estimate how many folds you might need. There are different ways to solve this problem, so it might help to show your interviewer how you thought through each step, no matter which way you choose.
“First, I’ll have to take a guess at how tall the Empire State Building is. I think it has about 100 floors, so if each floor is about 15 feet high, the whole building would be about 15,000 feet high. Now I can start thinking about how to do the math for the paper. I know that every time I fold it, it doubles in height. Let’s say that five folds of paper are equal to about 1 cm. If I fold it six times, it will be two centimetres long, and if I fold it seven times, it will be four centimetres long.
When the paper is folded eight times, it is eight centimetres long, nine times, it is sixteen centimetres long, and ten times, it is 32 centimetres long, which is about one foot. 11 folds is two feet, 12 folds is four feet, 13 folds is eight feet, 14 folds is 16 feet, 15 folds is 32 feet, 16 folds is 64 feet, 17 folds is 128 feet, 18 folds is 256 feet, 19 folds is 512 feet, 20 folds is 1,024 feet, 21 folds is 2,048 feet. So a piece of paper would have to be folded between 20 and 21 times to reach the height of the Empire State Building.”
7. Imagine that there are three light switches outside a room with a closed door. One of the switches makes the lights in the room come on and off. How can you figure out which light switch controls the light in a room if you can only go in there once?
Interviewers may ask this question to see how well a candidate can use numbers and logic to think outside the box. You might find it helpful to say out loud what you are thinking as you try to figure out the answer. This can show how smart you are even if you don’t fully answer the question.
If I flip one switch and then go into the room and see that the light is on, I know it was that switch. It could be one of the other two things if it doesn’t work. So, I wouldn’t know which switch turns the light on. Logic works the same way backwards if I turn on two switches. If the light is on, it could be either of the two switches I tried. That means the answer needs to be more creative.
I would probably turn on the first light and leave it on for 15 minutes. Then I would turn off the first light switch and turn on the second one. Then I would go into the room, and if the light was on, I would know that the second light switch controlled it. I would touch the bulb to see if it is on or off. When I tried the first switch, the light came on if the bulb was warm. The third light switch, which I hadn’t tried yet, controls the light bulb when it’s cold.