Today I had my first ib interview which went pretty well until these 2 brainteasers came up and showed my lack of mental math skills:
What is 3 to the power of 12 What is 5 to the power of 5.
No way I could do these in my head
| +197 | Americas M&A League Table Q2 Updated | 79 | 1h |
| +142 | New Article: Dramatic Slide as UBS #22 (US) & New Leadership Desperately Needed | 38 | 21h |
| +131 | Restructuring: Anti-climactic Experience | 34 | 1d |
| +101 | IB Net Worth / Savings Check | 47 | 9h |
| +91 | Woman who emptied Knicks trashcan on street then stole it was DEI exec, worked at JPMorgan Chase | 24 | 11h |
| +77 | Stop sleeping on UBS - it’s pretty good | 26 | 16m |
| +51 | 2026 VAULT PRESTIGE RANKINGS | 29 | 1d |
| +39 | AI + Financial Modelling | 12 | 22h |
| +28 | Summer before college | 17 | 11h |
| +27 | Hardest interview experiences? | 16 | 20h |
Career Resources
Get instant access to lessons taught by experienced private equity pros and bulge bracket investment bankers including financial statement modeling, DCF, M&A, LBO, Comps and Excel Modeling.
3^(2* 6)=9^(2* 3)=81^3= approx 80^3=6400*80=Approx > 512000
25* 25* 5=625*5=3125
So when somthing like 3 to the power of 12 comes up, I basically am not expected to calculate the exact number but rather approximate? Thank you!
I mean I wouldn't know how to do 81* 81* 81 in my head, just saying what I would say in an interview
Math major here. I always try this approach when I do those numbers in my head:
3^12 = (3^4)^3. Now 3^4 is 81, and you want 81^3. 81^3 = 81 * 81 * 81 = (80+1) * (80+1) * (80+1) In your head, it not hard to do (80 + 1) * (80 + 1) = 80^2 + 80 + 80 + 1 = 6561. The hard part is 6561 * 81. Try the same way above. 6561 * 81 = (6560 + 1) * (80 + 1) = 6560 * 80 + 6560 + 80 + 1. Now 6560 * 80, do 656 * 8 first. then put two 00s there. Then do the sum.
5^5 is easier. 25 ^ 2 = 625, 625 * 5 = 3125. Maybe I cheated, because as a Math major we are kinda supposed to know this one.
Hope this helps.
I am being honest here. I wouldn't be able to pull this off in my head without confusing the numbers
Alright. How did u answer the question during the interview?
http://arithmetic.lemo.education/ and learn. Mental math is an absolut classic in finance interviews, so just learn it. No big deal about it.
Id eaque omnis laboriosam. Qui sunt hic ipsam qui recusandae voluptas ut. Perferendis facere aut asperiores voluptatem quas eos modi.
Quia qui provident illo consequuntur nemo impedit ut. Et maxime libero pariatur et at dolore. Doloribus sit libero nam maxime dolore. Qui impedit ut aliquid voluptatem.
Ducimus aut facere consectetur commodi. Vero minima aperiam ut et facere rerum nostrum. Est dolores omnis nemo pariatur veniam.
See All Comments - 100% Free
WSO depends on everyone being able to pitch in when they know something. Unlock with your email and get bonus: 6 financial modeling lessons free ($199 value)
or Unlock with your social account...