Error with If then statement

Error with If then statement

I am having a problem with this statement. I am trying to populate the field Fee on my form based on the selection in the field Age_Group. 

if (input.Age_Group == "70 and Over")  
  {input.Fee = 115};
else if(input.Age_Group == "13 - 69")
  {input.Fee = 125};
else if(input.Age_group == "5 - 12")
   {input.Fee = 25};
else {input.Fee = 0};

The error is  Error at line number : 1  
Number of arguments mismatches

I searched the Forum and found a similar issue and put the semi-colons in but I am still getting the error.