PCEP Data Types, Variables, Basic I/O and Operators — Timed 100 Questions

Question 1

A developer writes the following code: x = 5; y = 2; print(x // y). What is the output?

Accepted Answer

2. The floor division operator (//) in Python returns the largest integer less than or equal to the result of the division. Since 5 divided by 2 equals 2.5, the floor is 2, and the result is an integer (int) because both operands are integers. Therefore, the output is 2.

Answer

1

Answer

2.0

Answer

2.5

Question 2

A junior developer writes: x = 10; y = 3; print(x % y). What will be printed?

Accepted Answer

1. The modulo operator (%) returns the remainder of the division of the left operand by the right operand. Here, 10 divided by 3 equals 3 with a remainder of 1, so print(x % y) outputs 1.

Answer

3.33

Answer

0

Answer

3

Question 3

A developer needs to convert a string '25' to an integer and then add 10. Which code correctly performs this?

Accepted Answer

print(int('25') + 10). Option A is correct because `int('25')` converts the string '25' to the integer 25, and then `+ 10` performs integer addition, resulting in 35. The `print()` function outputs the result. This follows Python's type conversion rules where explicit conversion is required to combine a string and an integer in arithmetic.

Answer

print('25' + 10)

Answer

print(int('25') + '10')

Answer

print('25' + str(10))

Question 4

What is the correct way to read a floating-point number from user input and store it in a variable?

Accepted Answer

x = float(input()). Option C is correct because `float(input())` first reads the user input as a string via `input()`, then converts that string to a floating-point number using the `float()` function. This is the standard and only valid way in Python to obtain a float from console input, as `input()` always returns a string.

Answer

x = input(float())

Answer

x = input() as float

Answer

x = input().float()

Question 5

A developer wants to assign the value 3.14 to a variable and later change it to the integer 3. Which of the following is true?

Accepted Answer

This is allowed because Python is dynamically typed.. Option C is correct because Python is dynamically typed, meaning variables can be reassigned to values of any type at runtime. The developer can first assign the float 3.14 to a variable and later reassign the integer 3 to the same variable without any type declaration or conversion function required.

Answer

This is allowed only if the variable was declared as a float.

Answer

This causes a TypeError because you cannot change types.

Answer

This is allowed only if you use the int() function during assignment.

Question 6

Which of the following is a valid variable name in Python?

Accepted Answer

_count. Option C (_count) is correct because in Python, variable names can start with an underscore, and underscores are allowed anywhere in the name. The name _count follows all Python identifier rules: it starts with a letter or underscore, contains only letters, digits, or underscores, and is not a reserved keyword.

Answer

my-var

Answer

2nd_place

Answer

class

Question 7

A developer writes: print(10 * '5'). What is the output?

Accepted Answer

5555555555. In Python, the multiplication operator (*) when used with a string and an integer performs string repetition. The expression 10 * '5' repeats the string '5' ten times, resulting in the string '5555555555'. The print() function then outputs this concatenated string without quotes.

Answer

10

Answer

50

Answer

5

Question 8

What is the result of the expression: print(2 ** 3 ** 2) ?

Accepted Answer

512. The expression `2 ** 3 ** 2` uses the exponentiation operator `**`, which in Python is right-associative. This means it is evaluated as `2 ** (3 ** 2)`, not `(2 ** 3) ** 2`. First, `3 ** 2` equals 9, then `2 ** 9` equals 512. Therefore, option A is correct.

Answer

256

Answer

64

Answer

128

Question 9

A beginner writes: x = '10'; y = 20; print(x + y). What happens?

Accepted Answer

Raises TypeError. Option A is correct because Python's type system does not allow implicit concatenation of a string and an integer. The variable `x` is a string (`'10'`), and `y` is an integer (`20`). The `+` operator with these types triggers a `TypeError: unsupported operand type(s) for +: 'int' and 'str'` (or vice versa), as Python refuses to guess the programmer's intent.

Answer

Prints 30

Answer

Prints 10 + 20

Answer

Prints 1020

Question 10

Which operator is used to check if two values are equal in Python?

Accepted Answer

==. Option D is correct because the == operator is Python's equality comparison operator, used to check if two values are equal. It returns True if the values are equal and False otherwise, making it the standard way to test equality in conditions and expressions.

Answer

=

Answer

eq

Answer

!=

Question 11

A developer writes: a = 3; b = 4; c = a + b / 2. What is the value of c?

Accepted Answer

5.0. In Python, the division operator `/` always returns a float, and operator precedence dictates that division is performed before addition. Thus, `b / 2` evaluates to `4 / 2 = 2.0`, then `a + 2.0` yields `3 + 2.0 = 5.0`. Option D is correct because the result is a float value of 5.0.

Answer

3

Answer

3.5

Answer

5

Question 12

Which TWO of the following are valid ways to create a variable with the integer value 100?

Accepted Answer

x = int('100'). Option C is correct because the `int()` function converts a string containing a valid integer literal, such as '100', into an integer value of 100. This is a standard type-casting operation in Python that explicitly creates an integer from a string representation.

Answer

x = 0100

Answer

x = 100.0

Answer

x = '100'

Question 13

Which THREE of the following expressions evaluate to True?

Accepted Answer

3 == 3. Option A is correct because the equality operator '==' compares the integer values 3 and 3, which are identical, so the expression evaluates to True. In Python, '==' checks for value equality, not identity, and since both operands are the same integer literal, the result is True.

Answer

1 < 0

Answer

4 > 5

Question 14

Which TWO of the following are valid Python data types?

Accepted Answer

str. Option B (str) is correct because Python uses 'str' as its built-in type for textual data, which is a sequence of Unicode characters. This is a fundamental data type in Python, distinct from other languages that might use 'string' or 'char'.

Answer

real

Answer

array

Answer

char

Question 15

Which THREE of the following are correct uses of the print() function?

Accepted Answer

print('Hello', 'World', sep='-'). Option B is correct because the print() function in Python 3 accepts a 'sep' keyword argument that specifies the separator between multiple arguments. Here, sep='-' causes the output to be 'Hello-World', demonstrating a valid and commonly used feature of print().

Answer

print 'Hello'

Answer

print('Hello', 5)

Question 16

What is the output of the code?

Accepted Answer

. The expression `3 / 2` performs true division in Python, which always returns a float even if both operands are integers. The result is `1.5`, and `type(1.5)` returns ``. Therefore, option B is correct.

Answer

Answer

Answer

Question 17

A user enters 'Alice' for name and '30' for age. What is the output?

Accepted Answer

Alice is 30 years old.. Option A is correct because the code `print(name + ' is ' + age + ' years old.')` concatenates the string `'Alice '`, the string `' is '`, the string `'30'`, and the string `' years old.'` using the `+` operator. In Python, the `+` operator performs string concatenation when both operands are strings, and since `input()` always returns a string, both `name` and `age` are strings, so no type error occurs. The output is exactly `Alice is 30 years old.` including the period at the end.

Answer

Alice is 30 years old

Answer

Error: cannot concatenate str

Answer

Name: Alice, Age: 30

Question 18

What is the data type of z?

Accepted Answer

float. The data type of z is float because the expression 10 / 3 performs true division in Python, which always returns a float even if the operands are integers. The result of 10 / 3 is approximately 3.3333333333333335, a floating-point number.

Answer

bool

Answer

int

Answer

str

Question 19

You are a junior developer at a logistics company. Your team is building a system to calculate shipping costs based on package weight. The system reads weight from user input. A colleague wrote the following code: weight = input('Enter weight in kg: '); cost = weight * 2.5; print('Shipping cost:', cost). However, when testing with weight 10, the output is 'Shipping cost: 10101010101010101010' (the string '10' repeated 2.5 times? Actually, 2.5 is float, but string multiplied by float causes TypeError? Wait, string * float raises TypeError. But the symptom described suggests the code runs but produces unexpected output. Let me re-read: The output shows '10101010101010101010' which is the string '10' repeated 10 times? That would happen if weight is string and multiplied by int 10. But the code multiplies by 2.5. Actually, string * float raises TypeError, so the code would crash. The symptom must be plausible. Let me adjust: The code actually has weight = input(...), then cost = weight * 2.5, but if weight is '10', then '10' * 2.5 raises TypeError. So the symptom cannot be that output. I need to fix the stem to make sense. Instead, let's say the code is: weight = input('Enter weight: '); cost = float(weight) * 2.5; print('Cost:', cost). But then no issue. I'll create a scenario where the developer forgot to convert input to float, and then tries to multiply string by float, which causes TypeError. The correct action is to convert input to float. I'll adjust the stem accordingly. Let me rewrite the stem properly.

Stem: You are a developer at a shipping company. The system calculates shipping cost as weight (kg) times rate 2.5. A colleague wrote: weight = input('Enter weight: '); cost = weight * 2.5; print('Cost:', cost). When testing with weight 10, the program crashes with TypeError. Which action should you take to fix the code?

Accepted Answer

Change weight = float(input('Enter weight: ')). Option D is correct because `input()` always returns a string, and multiplying a string by a float (2.5) raises a `TypeError`. Converting the input to `float` ensures the multiplication is numeric, allowing decimal weights and producing the correct shipping cost.

Answer

Change weight = int(input('Enter weight: '))

Answer

Change cost = weight * 2.5 and catch TypeError

Answer

Change cost = int(weight) * 2.5

Question 20

You are a data analyst at a retail company. You have a list of sales figures stored as strings in a list: sales = ['100', '200', '300']. You need to calculate the total sum. A colleague suggests using: total = sum(sales). However, this raises a TypeError because sum() requires numeric values. Which approach should you take to correctly calculate the total as an integer?

Accepted Answer

Use total = sum(int(s) for s in sales). Option B is correct because it uses a generator expression to convert each string element in the `sales` list to an integer via `int(s)` before passing the resulting integers to `sum()`. The `sum()` function requires numeric operands; passing strings directly causes a `TypeError`. By converting to integers first, the total is correctly computed as an integer.

Answer

Use total = sum(sales) and catch TypeError

Answer

Use total = 0; for s in sales: total += s