What is wrong for each of the following program segments?

if(age > 13)
   ticketPrice = 10;   //For regular adults
else
   if(age > = 60)      //There is no chance to execute this part
     ticketPrice = 6;  //For seniors

Think: how much of ticket price will a 65-years old man pay?

if(score >= 90)
   grade = 'A';
if(score >= 80)     //Every score needs to be checked at this point.
   grade = 'B';     //Some grades may be overwritten.
if(score >= 70)
   grade = 'C';
if(score >= 60)
   grade = 'D';
else
   grade = 'F';

Think: what grade will a score, 95 be?