How to calculate total summary of result in angularjs

I have 3 inputs  and a Add button in table grid, i want to calculate  val1 , val2, save result in result input and add new row on Add button click

 

 i have another input Total summery in another row , if i have 3  results in above  , i want to calculate total result and show in TotalAmount 

 

here i have code

 

 

https://jsbin.com/huxocezani/1/edit?html,js,output