Vishakan with his proud parents and MBR representatives, who presented him with a certificate last Friday. (Bernama pics) PETALING JAYA: Most six-year-olds spend car rides gazing out the window or asking how much longer it will take to reach their destination. Vishakan Thanarajan does something different. As vehicles pass by, he studies their registration numbers and turns them into multiplication questions in his head. It’s a habit that has fas…