What's the voting math at the centre of the Tata Group power struggle?

The board meeting at Tata Sons saw Noel Tata and Venu Srinivasan, Chairman and Vice Chairman of the company's owner Tata Trusts, vote against each other over N Chandrasekaran's reappointment. Board members Saurabh Agrawal and Anita Marangoly George voted in favour, while Chandrasekaran skipped voting on his own reappointment. The deciding vote was cast by independent director Harish Manwani.