Finance Brain Teasers — Investment Banking Mock Interview
Work through time-value-of-money puzzles, beta logic problems, bond YTM calculations, and capital structure scenarios tested in real IB interviews.
Preview This Mock Interview
60-second preview — upgrade to Diamond for full sessions
Key Topics Covered
Time Value of Money & Perpetuity Puzzles
Covers lump-sum versus perpetuity trade-offs at different discount rates, finite annuity comparisons, the present value of a dollar per day forever, and how counterparty creditworthiness changes your willingness to pay.
Bond Math & Yield to Maturity
Walks through YTM calculations for one-year, two-year, and three-year bonds using pen-and-paper approximation methods, explains the relationship between coupon rate and YTM when bonds trade at a discount, and covers how YTM changes as maturity shortens.
Beta, Risk & Capital Structure Logic
Tests whether you understand why a coin-flip company can have lower beta than a refrigerator manufacturer, the beta of a gambling ring, negative-beta assets, and how operating and financial leverage affect equity beta within the same industry.
FCF, Terminal Value & Margin Analysis
Ranks the impact of revenue increases, D&A decreases, and capex reductions on free cash flow and terminal value. Explores why a company might willingly accept lower margins, and walks through EBITDA sensitivity to revenue changes under different cost structures.
Creative Valuation & Deal Scenarios
Includes valuing a hot dog stand and a building using comps, precedents, and DCF. Also covers M&A cash-versus-stock mix calculations, a conglomerate undervaluation and divestiture strategy, and matching preferred equity, convertible debt, and senior secured debt to different company profiles.
How to Prepare for Finance Brain Teasers Interviews
Memorize the perpetuity formula (PV = C / r) and the annuity present value formula cold, then practice comparing lump sums to payment streams at varying discount rates. These recordings show that interviewers layer complexity by changing the rate, the time horizon, or the counterparty risk to test your flexibility.
Practice approximating bond YTM without a calculator using the shortcut: (annual coupon + annualized capital gain) divided by the average of face value and price. The advanced session demonstrates this across one-, two-, three-, and four-year maturities, so drill until the mechanics are automatic.
Build intuition for the distinction between total risk and systematic risk by working through examples of high-volatility but zero-beta assets like lottery tickets and gambling, versus lower-volatility but higher-beta assets like cyclical manufacturers. Interviewers test this distinction repeatedly.
When asked about the impact of financial statement changes on FCF or valuation, always think through the tax effect first. A decrease in D&A actually hurts free cash flow because you lose the tax shield, and interviewers use this as a trap question to separate candidates who think mechanically from those who just memorize formulas.
More Core Concepts Topics
View allAccounting
Covers foundational accounting concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
Enterprise & Equity Value
Covers foundational enterprise & equity value concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
Discounted Cash Flow (DCF)
Covers foundational dcf concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
Valuation
Covers foundational valuation concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
Leveraged Buyouts (LBO)
Covers foundational leveraged buyouts (lbos) concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
Mergers & Acquisitions (M&A)
Covers foundational merger model (m&a) concepts commonly tested in investment banking interviews. Discusses key definitions, frameworks, and walk-through questions at an introductory level.
About This Finance Brain Teasers Mock Interview
These two sessions cover over 40 finance brain teasers spanning total return calculations, compound interest, working capital mechanics, FCFE versus FCFF distinctions, perpetuity and annuity valuation, bond yield-to-maturity at varying maturities, duration, DCF sensitivity analysis, deleveraging strategies, IRR versus MOIC comparisons, operating leverage trade-offs, the impact of D&A, capex, and revenue changes on free cash flow and terminal value, matching investment structures to company profiles, regression-based valuation, and creative valuation exercises including a hot dog stand and a building.
This topic is part of the Core Concepts section of our investment banking mock interview library. It includes 2 sessions covering both basic and advanced difficulty levels. Each session includes multi-speaker audio with realistic interviewer questions and candidate responses, plus a full interactive transcript you can follow along with or study independently.
Audio Recording
59 minutes of multi-speaker audio
Full Transcript
Interactive transcript with timestamps
1 Basic + 1 Advanced
Basic & Advanced
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Moelis & Co.
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Perella Weinberg
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Cantor Fitzgerald
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Barclays
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TD Securities
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Citadel
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Piper Sandler
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Lazard
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Houlihan Lokey
“IB Vine was the most helpful resource I had during recruiting. I will continue to promote it to other students at WashU and elsewhere.”
Jefferies
“Awesome product, helped me crush my technicals in my interviews and land a great role. Thank you, seriously was a huge help.”
Morgan Stanley
“Very helpful to get real-life questions unlike the 400 guide, especially for merger math. Built deeper understanding of key concepts.”
Houlihan Lokey
“Extremely helpful study tool that carried me through the recruitment process from start to end.”
Evercore
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Rothschild
“IB Vine was incredibly helpful and I am forever thankful for all the help.”
RBC
“IB Mock was amazing - I used it for multiple hours. Also the flashcards and the lessons features on IB Vine were fantastic. Thank you!”
Dragoneer
“IB Vine is such a great platform, really impressive. There is so much value in this. The audio podcasts / mock interview library are pretty incredible.”
Moelis & Co.
“I loved IB Vine. I’m going into Private Capital Advisory (PCA); you have the lessons on there for PCA and that was actually a game changer. I went into those interviews and knew about the core PCA concepts like net asset value, primary fundraising vs. secondary advisory, etc. I swear I was on IB Vine like a few hours a day. The opportunity to have that learning section and go through the questions people submit and everything — there’s no better tool out there. I loved the guides/lessons. The user interface is amazing. The way you’ve simplified it is so spectacular — it’s just so much easier to digest. It’s fun to use too; I’d rather use IB Vine than scroll through a guide. To be honest, I think the product is perfect. I genuinely owe you a big thanks.”
Moelis & Co.
“IB Vine is a tool we really love to use in the club I’m a part of, and there’s really no other resource like it. You guys do a phenomenal job with the question bank. I recruited specifically for Energy banking, and IB Vine was my most used resource for generalist questions (which were about 50% of my interview questions; the rest being Energy-specific); the majority of such questions I saw in interviews were at least similar (if not the same) to the ones on IB Vine.”
Perella Weinberg
“Once I read through the BIWS learning guides, I really didn’t refer to them again. I didn’t even really run through the 400 question guide once I found IB Vine, which I heard about through one of my classmates. We even get a free subscription (like most business schools) to Wall Street Prep, and if I’m being completely honest, I never even logged in to WSP. IB Vine is pretty much the only tool I used (along with our club question bank & mock interviews with peers) and it was invaluable for recruiting.”
Cantor Fitzgerald
“What a platform, made such a huge difference. I did superdays at Evercore, PJT, M. Klein and Barclays among others from a non-target school and did not miss a single technical in any interview process through prepping with IB Vine.”
Barclays
“Very accurate questions and all of the solutions are easy to follow. At least 10 of the questions I studied through this platform appeared in my Round 1 or Superday interviews.”
TD Securities
“THANK YOU SO MUCH IB VINE, I COULD NOT HAVE DONE THIS WITHOUT YOU, SERIOUSLY!!! IB Vine was the best website ever. I spent at least two hours on this daily (seriously) from October through I get my offer in February.”
Citadel
“I’m doing public equities this summer and next. I know the name is “IB Vine” but at the undergrad level a lot of the technicals across public equities are the same as investment banking. I recommend your software to all my friends!”
Piper Sandler
“I loved this site! 1000% this is the best resource I used in the process.”
Lazard
“This was the greatest tool ever. I genuinely enjoyed running through the technicals/behaviorals and it was very helpful!”
Houlihan Lokey
“IB Vine was the most helpful resource I had during recruiting. I will continue to promote it to other students at WashU and elsewhere.”
Jefferies
“Awesome product, helped me crush my technicals in my interviews and land a great role. Thank you, seriously was a huge help.”
Morgan Stanley
“Very helpful to get real-life questions unlike the 400 guide, especially for merger math. Built deeper understanding of key concepts.”
Houlihan Lokey
“Extremely helpful study tool that carried me through the recruitment process from start to end.”
Evercore
“You guys are doing great work over there with IB Vine. Absolute staple for interview prep.”
Rothschild
“IB Vine was incredibly helpful and I am forever thankful for all the help.”
RBC
“IB Mock was amazing - I used it for multiple hours. Also the flashcards and the lessons features on IB Vine were fantastic. Thank you!”
Dragoneer
“IB Vine is such a great platform, really impressive. There is so much value in this. The audio podcasts / mock interview library are pretty incredible.”
Moelis & Co.
“I loved IB Vine. I’m going into Private Capital Advisory (PCA); you have the lessons on there for PCA and that was actually a game changer. I went into those interviews and knew about the core PCA concepts like net asset value, primary fundraising vs. secondary advisory, etc. I swear I was on IB Vine like a few hours a day. The opportunity to have that learning section and go through the questions people submit and everything — there’s no better tool out there. I loved the guides/lessons. The user interface is amazing. The way you’ve simplified it is so spectacular — it’s just so much easier to digest. It’s fun to use too; I’d rather use IB Vine than scroll through a guide. To be honest, I think the product is perfect. I genuinely owe you a big thanks.”
Moelis & Co.
“IB Vine is a tool we really love to use in the club I’m a part of, and there’s really no other resource like it. You guys do a phenomenal job with the question bank. I recruited specifically for Energy banking, and IB Vine was my most used resource for generalist questions (which were about 50% of my interview questions; the rest being Energy-specific); the majority of such questions I saw in interviews were at least similar (if not the same) to the ones on IB Vine.”
Perella Weinberg
“Once I read through the BIWS learning guides, I really didn’t refer to them again. I didn’t even really run through the 400 question guide once I found IB Vine, which I heard about through one of my classmates. We even get a free subscription (like most business schools) to Wall Street Prep, and if I’m being completely honest, I never even logged in to WSP. IB Vine is pretty much the only tool I used (along with our club question bank & mock interviews with peers) and it was invaluable for recruiting.”
Cantor Fitzgerald
“What a platform, made such a huge difference. I did superdays at Evercore, PJT, M. Klein and Barclays among others from a non-target school and did not miss a single technical in any interview process through prepping with IB Vine.”
Barclays
“Very accurate questions and all of the solutions are easy to follow. At least 10 of the questions I studied through this platform appeared in my Round 1 or Superday interviews.”
TD Securities
“THANK YOU SO MUCH IB VINE, I COULD NOT HAVE DONE THIS WITHOUT YOU, SERIOUSLY!!! IB Vine was the best website ever. I spent at least two hours on this daily (seriously) from October through I get my offer in February.”
Citadel
“I’m doing public equities this summer and next. I know the name is “IB Vine” but at the undergrad level a lot of the technicals across public equities are the same as investment banking. I recommend your software to all my friends!”
Piper Sandler
“I loved this site! 1000% this is the best resource I used in the process.”
Lazard
“This was the greatest tool ever. I genuinely enjoyed running through the technicals/behaviorals and it was very helpful!”
Houlihan Lokey
“IB Vine was the most helpful resource I had during recruiting. I will continue to promote it to other students at WashU and elsewhere.”
Jefferies
“Awesome product, helped me crush my technicals in my interviews and land a great role. Thank you, seriously was a huge help.”
Morgan Stanley
“Very helpful to get real-life questions unlike the 400 guide, especially for merger math. Built deeper understanding of key concepts.”
Houlihan Lokey
“Extremely helpful study tool that carried me through the recruitment process from start to end.”
Evercore
“You guys are doing great work over there with IB Vine. Absolute staple for interview prep.”
Rothschild
“IB Vine was incredibly helpful and I am forever thankful for all the help.”
RBC
“IB Mock was amazing - I used it for multiple hours. Also the flashcards and the lessons features on IB Vine were fantastic. Thank you!”
Dragoneer
“IB Vine is such a great platform, really impressive. There is so much value in this. The audio podcasts / mock interview library are pretty incredible.”
Moelis & Co.
“I loved IB Vine. I’m going into Private Capital Advisory (PCA); you have the lessons on there for PCA and that was actually a game changer. I went into those interviews and knew about the core PCA concepts like net asset value, primary fundraising vs. secondary advisory, etc. I swear I was on IB Vine like a few hours a day. The opportunity to have that learning section and go through the questions people submit and everything — there’s no better tool out there. I loved the guides/lessons. The user interface is amazing. The way you’ve simplified it is so spectacular — it’s just so much easier to digest. It’s fun to use too; I’d rather use IB Vine than scroll through a guide. To be honest, I think the product is perfect. I genuinely owe you a big thanks.”
Moelis & Co.
“IB Vine is a tool we really love to use in the club I’m a part of, and there’s really no other resource like it. You guys do a phenomenal job with the question bank. I recruited specifically for Energy banking, and IB Vine was my most used resource for generalist questions (which were about 50% of my interview questions; the rest being Energy-specific); the majority of such questions I saw in interviews were at least similar (if not the same) to the ones on IB Vine.”
Perella Weinberg
“Once I read through the BIWS learning guides, I really didn’t refer to them again. I didn’t even really run through the 400 question guide once I found IB Vine, which I heard about through one of my classmates. We even get a free subscription (like most business schools) to Wall Street Prep, and if I’m being completely honest, I never even logged in to WSP. IB Vine is pretty much the only tool I used (along with our club question bank & mock interviews with peers) and it was invaluable for recruiting.”
Cantor Fitzgerald
“What a platform, made such a huge difference. I did superdays at Evercore, PJT, M. Klein and Barclays among others from a non-target school and did not miss a single technical in any interview process through prepping with IB Vine.”
Barclays
“Very accurate questions and all of the solutions are easy to follow. At least 10 of the questions I studied through this platform appeared in my Round 1 or Superday interviews.”
TD Securities
“THANK YOU SO MUCH IB VINE, I COULD NOT HAVE DONE THIS WITHOUT YOU, SERIOUSLY!!! IB Vine was the best website ever. I spent at least two hours on this daily (seriously) from October through I get my offer in February.”
Citadel
“I’m doing public equities this summer and next. I know the name is “IB Vine” but at the undergrad level a lot of the technicals across public equities are the same as investment banking. I recommend your software to all my friends!”
Piper Sandler
“I loved this site! 1000% this is the best resource I used in the process.”
Lazard
“This was the greatest tool ever. I genuinely enjoyed running through the technicals/behaviorals and it was very helpful!”
Houlihan Lokey
“IB Vine was the most helpful resource I had during recruiting. I will continue to promote it to other students at WashU and elsewhere.”
Jefferies
“Awesome product, helped me crush my technicals in my interviews and land a great role. Thank you, seriously was a huge help.”
Morgan Stanley
“Very helpful to get real-life questions unlike the 400 guide, especially for merger math. Built deeper understanding of key concepts.”
Houlihan Lokey
“Extremely helpful study tool that carried me through the recruitment process from start to end.”
Evercore
“You guys are doing great work over there with IB Vine. Absolute staple for interview prep.”
Rothschild
“IB Vine was incredibly helpful and I am forever thankful for all the help.”
RBC
“IB Mock was amazing - I used it for multiple hours. Also the flashcards and the lessons features on IB Vine were fantastic. Thank you!”
Dragoneer
“IB Vine is such a great platform, really impressive. There is so much value in this. The audio podcasts / mock interview library are pretty incredible.”
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