Mckinsey Data Science Interview (First Round)

Dear all,

I have a coming interview with Mckinsey: (please see below)

Interview Structure

You will have 2 First Round interviews and will virtually meet with our consultants for approximately 50 minutes each. Each of your interviews will consist of the following components: 

Interview 1: Blended PSS (includes Technical Knowledge)

Interview 2: PEI (Personal Impact) + TEI

It seems that preparation is endless as there is so much to do. I have done about 20 live  cases. I am starting to prepare the PEI questions and Answers (that seems endess too). Anything else i can do to increase my chances? Any reference you can share with me? 

Thank you