Python Activity 3:  Arithmetic Operations and Assignment Statements 
                                                        "Get the program to compute that!" 
                                                    "How do I assignment values to variables?" 
                   
                       Learning Objectives 
                       Students will be able to: 
                       Content: 
                          Explain each Python arithmetic operator 
                          Explain the meaning and use of an assignment statement 
                          Explain the use of "+"  and "*" with strings and numbers 
                          Use the int()  and float() functions to convert string input to numbers for computation 
                          Incorporate numeric formatting into print statements 
                          Recognize the four main operations of a computer within a simple Python program 
                       Process: 
                          Create input statements in Python 
                          Create Python code that performs mathematical and string operations 
                          Create Python code that uses assignment statements 
                          Create Python  code that formats numeric output 
                        
                       Prior Knowledge 
                          Understanding of Python print and input statements 
                          Understanding of mathematical operations 
                          Understanding of flowchart input symbols 
                        
                       Further Reading 
                          https://en.wikibooks.org/wiki/Non-Programmer%27s_Tutorial_for_Python_3/Hello,_World  
                          https://en.wikibooks.org/wiki/Non-
                           Programmer%27s_Tutorial_for_Python_3/Who_Goes_There%3F  
                   
                                                       
                           Model 1: Arithmetic Operators in Python 
                           Python includes several arithmetic operators: addition, subtraction, multiplication, two types of division, 
                           exponentiation and mod. 
                                                                Flowchart                                                                                Python Program 
                                                                                                                                # Programmer: Monty Python 
                                                                                                                                # Date: Sometime in the past 
                                                                                                                                # Description: A program 
                                                                                                                                # explores arithmetic operators 
                                                                                                                                 
                                                                                                                                print(16+3) 
                                                                                                                                 
                                                                                                                                print(16-3) 
                                                                                                                                 
                                                                                                                                print(16*3) 
                                                                                                                                 
                                                                                                                                print(16**3) 
                                                                                                                                 
                                                                                                                                print(16/3) 
                                                                                                                                 
                                                                                                                                print(16//3) 
                                                                                                                                 
                                                                                                                                print(16.0/3) 
                                                                                                                                 
                                                                                                                                print(16.0//3) 
                                                                                                                                 
                                                                                                                                print(16%3) 
                                                                                                                                 
                            
                           Critical Thinking Questions: 
                           1. Draw a line between each flowchart symbol and its corresponding line of Python code. Make note of 
                                 any problems. 
                                  
                           2. Execute the print statements in the previous Python program.  
                                                     a.    Next to each print statement above, write the output. 
                                                            
                                                     b.  What is the value of the following line of code? 
                                                           print((16//3)*3+(16%3)) 
                                                            
                                                     c.    Predict the values of 17%3 and 18%3 without using your computer. 
                                  
                           3. Explain the purpose of each arithmetic operation: 
                                 a.                  +            ____________________________ 
                                 b.                  -            ____________________________ 
                                 c.                  *            ____________________________ 
                                 d.                  **           ____________________________ 
                                 e.                  /            ____________________________ 
                                 f.                  //           ____________________________ 
                                 g.                  %            ____________________________ 
                     Information: Assignment Statements 
                                  An assignment statement is a line of code that uses a "=" sign. The statement stores the result 
                               of an operation performed on the right-hand side of the sign into the variable memory location 
                            on the left-hand side. 
                      4.  Enter and execute the following lines of Python code in the editor window of your IDE (e.g. Thonny): 
                     MethaneMolMs = 16                                 Python Program 1 
                     EthaneMolMs = 30 
                     print("The molecular mass of methane is", MethaneMolMs) 
                     print("The molecular mass of ethane is", EthaneMolMs) 
                           
                           
                          a.   What are the variables in the above python program? 
                                
                                
                          b.  What does the assignment statement: MethaneMolMs = 16 do? 
                        
                        
                          c.   What happens if you replace the comma (,) in the print statements with a plus sign (+) and 
                               execute the code again?  Why does this happen? 
                      
                      
                     5.        What is stored in memory after each assignment statement is executed? 
                                
                                                Assignment Statement                        Computer Memory 
                                             answer =  6 ** 2 + 3 * 4 // 2              answer          
                                             final = answer % 4                         final           
                      
                     Information: Concatenating Strings in Python 
                                The "+" concatenates the two strings stored in the variables into one string.  "+" can only be 
                              used when both operators are strings. 
                      
                     6.        Run the following program in the editor window of your IDE (e.g. Thonny) to see what happens 
                     if you try to use the "+" with strings instead of numbers? 
                                
                         firstName = "Monty"                               Python Program 2 
                         lastName = "Python" 
                         fullName = firstName + lastName 
                         print(fullName) 
                         print(firstName,lastName) 
                          
                          a.   The third line of code contains an assignment statement. What is stored in fullName when the 
                               line is executed? 
                                
                                
                                
                          b.  What is the difference between the two output lines? 
                                
                                
                          c.   How could you alter your assignment statements so that print(fullName)gives the same 
                               output as print(firstName,lastName) 
                      
                      
                          d.  Only one of the following programs will work. Which one will work, and why doesn’t the other 
                               work? Try doing this without running the programs! 
                                          
                                  Python Program 3                                                Python Program 4 
                addressNumber = 1600                                            addressNumber = "1600" 
                streetName = "Pennsylvania Ave"                                 streetName = "Pennsylvania Ave" 
                streetAddress= addressNumber + streetName                       streetAddress= addressNumber + streetName 
                print(streetAddress)                                            print(streetAddress) 
                        
                        
                        
                        
                        
                        
                          e.   Run the programs above and see if you were correct. 
                                
                          f.   The program that worked above results in no space between the number and the street name. How 
                               can you alter the code so that it prints properly while using a concatenation operator? 
                      
                      
                      
                        
                     7.    Before entering the following code into the Python interpreter (Thonny IDE editor window), predict 
                          the output of this program. 
                                   Python Program 5                                               Predicted Output 
                           myNumber = "227" * 10   
                           print(myNumber) 
                           myWord = "Cool!" * 10 
                           print(myWord) 
                            
                      
                          Now execute it.  What is the actual output? Is this what you thought it would do? Explain.