Hi there,

A very common problem among candidates, which is relatively easy to train. Here's some thoughts on the matter:

1. The mental math tool on Preplounge is great. Also, Rocketblocks is pretty good for quant. Get access to these tools asap and use them whenever you can e.g., to wind down after a long day of case cracking…
2. Write down random numbers on a sheet of paper with different operators and start practicing! You can make it complex with lots of numbers, operators, maybe even a variable to solve for, etc. Nothing beats practice, and if you're far from where you need to be, you need plenty of practice! Also, using paper will serve you well in the interviews, where you will working paper based.
3. Arithmetic i.e., execution, is just one of the steps you need to get right for a great quant score. There's generally more steps that you shouldn't neglect (but lots of candidates do…), breaking down into the following:
   1. Identifying opportunities to do math when you're not specifically being asked e.g., you get an excibit with lots of numbers. Do you have the drive to crunch some numbers to device some non-obvious insights or are you just going to talk all day about all those numbers without calculating anything?
   2. Setting up an equation is something you have to learn, whether math is self-prompted or when you're being asked a specific question. This can often include solving for a variable x, so you need to get comfortable with longer equations and unknowns.
   3. Doing arithmetic, as described above, is the execution part and just one step in a sequence that you have to get right to show great quant skills.
   4. Contextualizing the result is not necessarily a quant skills and falls more in the conceptual skills domain, but it something that you absolutely have to get right! There's nothing worse than an interviewee giving me a number like I'm a teacher doing a math test. You need to use the output to inform either the next step or a certain insight.

Hope this helps a bit. Best of luck!

Moritz

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