At line 5, we have created a wrapper object of double by passing 120D, which is convertible to a Double, so there won't be any exception there.
But if you check carefully, you can see the variable number is declared inside try block, so the scope of the variable number is limited to that block, so trying to access it outside causes a compile time error.
httpsy/docs.oracle.com/javase/tutorial/iava/nutsandbolts/variables.html