Python Semester Independant Review Part 1

Front

What is the final result of the expression 4 + 5 * 3?

Back

19

Answer explanation

To solve 4 + 5 * 3, follow the order of operations: first multiply 5 by 3 to get 15, then add 4. Thus, 4 + 15 equals 19, making 19 the correct answer.

Front

What is the final result of the expression 7 / 2 + 6?

Back

9.5

Answer explanation

To solve 7 / 2 + 6, first calculate 7 / 2 which equals 3.5. Then add 6: 3.5 + 6 = 9.5. Therefore, the final result is 9.5.

Front

Choose the print statement below that will cause an error. Assume that num has the value 6, and name has the value "Isabella". Options: print(name + ":" ), print(num), print(name + " wants " + "num " + "candies"), print(name + ": " + str(num)), print(name + ": " + num)

Back

print(name + ": " + num)

Answer explanation

The statement print(name + ": " + num) will cause an error because num is an integer and cannot be concatenated directly with strings. It needs to be converted to a string using str(num) first.

Front

Which one of the statements below will cause an error? ans = "hi" * 8, ans = "hi" + 9, ans = "hi" + "hi" + "hi", ans = ("a" * 4) + "b"

Back

ans = "hi" + 9

Answer explanation

The statement 'ans = "hi" + 9' will cause an error because you cannot concatenate a string with an integer in Python. The other statements are valid operations.

Front

Suppose you have a variable defined a = "4". What is the variable type of a?

Back

str

Answer explanation

The variable a is defined as a string with the value '4'. In Python, enclosing a value in quotes indicates it is a string, not an integer or float. Therefore, the correct type of a is str.

Front

Choose the option that correctly prints out the variable(s).
x = "codehs"
print(int(x))

Back

The program will cause an error because "codehs" cannot be converted to an integer.

Answer explanation

The correct choice is that the program will cause an error because 'codehs' cannot be converted to an integer. The int() function requires a string that represents a valid integer, which 'codehs' does not.

Front

What kind of data does a float variable contain?

Back

Numbers that can have decimal components

Answer explanation

A float variable in programming, including Python, is designed to store numbers that can have decimal components, making it suitable for representing fractional values. Therefore, the correct choice is 'Numbers that can have decimal components'.

Front

What is the final result of the expression 2**3?

Back

8

Answer explanation

The expression 2**3 means 2 raised to the power of 3. This equals 2 * 2 * 2, which results in 8. Therefore, the correct answer is 8.

Front

What is the character that in-line Python comments begin with?

Back

#

Answer explanation

In-line Python comments begin with the '#' character. This symbol indicates that the rest of the line is a comment and will not be executed as code, making it the correct choice among the options provided.

Front

What is the difference between a binary operator and a unary operator?

Back

A binary operator needs two things, while a unary operator only needs one.

Answer explanation

A binary operator requires two operands to perform an operation (e.g., addition), while a unary operator requires only one operand (e.g., negation). Thus, the correct choice is that a binary operator needs two things, while a unary operator only needs one.