Career & Application at McKinsey & Company

Yesterday I got my final round at McKinsey, during 1st round I got pretty good feedback, they told me I nailed the cases and I was really strong at maths, during final round I also nailed the 1st interview but struggled during the 2nd one.

I did one math mistake that made me lose around 40 secs until I realized I was going the wrong way do to not taking 1 assumption but was able to remade it myself.

Is it normal to get an offer with 1 mistake like those? When it came to structuring it was pretty MECE and the rest of the case was pretty good with solid insights, is that enough to make it happen?

Hello community. I would like to ask for a source with mathematical tests like those in Mckinsey's recruitment process. Do you know where I can find test like those ones?

After college, where I obtained a 1-year master's degree in the UK, I pursued an entrepreneurial road and worked on multiple projects. While my CV overall looks good (good education, grades, international experience etc.), I do lack big brand names/office experience.

I recently joined a startup (about 50 people work there) in BD and can possibly switch to a more strategic role within the company in a few months.

However, I'm wondering what my best approach would be considering that my goal is still management consulting.

I also applied to a few smaller consulting firms. I haven't heard back from them yet.

Assuming that the smaller firms might also reject me, from what I see so far, my only option would be to try to get into a good MBA program and try to get a big name internship while doing my MBA. Would that be my best/only option?

Thank you for your advice!