Three motorcycle convoy riders went into a roadside food truck. One rider purchased four keropok lekor, a cup of coffee, and ten doughnuts for RM8.45. Another rider purchased three keropok lekor, a cup of coffee, and seven doughnuts for RM6.30. What did the third motorcycle rider pay for a keropok lekor, a cup of coffee, and a doughnut? (6 marks)