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Python basics MCQ questions with answers

Variables, data types, type conversion and print: pick an answer to see why it is right.

0 of 20 answered

  1. Question 1 · Easy

    What is the output of this code?

    x = 5
y = "5"
print(type(x), type(y))
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    Answer: B

    type() returns a class, which prints as <class 'int'>. The quotes make y a string, so its type is str. The <type ...> form is how Python 2 printed types.

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  2. Question 2 · Easy

    What is the output of this code?

    print("A", "B", "C", sep="-", end="|")
print("D")
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    Answer: A

    sep goes between the values and end replaces the usual newline, so the first call prints A-B-C| without a line break. The second print continues on the same line.

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  3. Question 3 · Easy

    What is the output of this code?

    print(int(7.9), int(-7.9))
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    Answer: C

    int() drops the fractional part, which truncates toward zero: 7.9 becomes 7 and -7.9 becomes -7. It does not round, and it does not floor -7.9 down to -8.

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  4. Question 4 · Easy

    What is the output of this code?

    a = "3"
b = "4"
print(a + b)
print(int(a) + int(b))
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    Answer: D

    + on two strings joins them, giving 34. After int() converts both values, + adds numbers and gives 7.

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  5. Question 5 · Easy

    What is the output of this code?

    price = 49.5
qty = 3
print(f"Total: {price * qty:.2f}")
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    Answer: B

    The f-string evaluates price * qty (148.5), and the format spec .2f shows exactly two decimal places, so it prints 148.50. Without the f prefix the braces would print as typed.

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  6. Question 6 · Medium

    What is the output of this code?

    print(bool("False"), bool(0.0), bool(" "))
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    Answer: C

    Any non-empty string is truthy, even "False" and a single space; only the empty string "" is falsy. 0.0 is zero, so bool(0.0) is False.

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  7. Question 7 · Medium

    What is the output of this code?

    a, b = 10, 20
a, b = b, a + b
print(a, b)
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    Answer: D

    The right-hand side is evaluated in full before anything is assigned, so a + b uses the old values (10 + 20). Doing the two assignments one after the other would give 20 40.

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  8. Question 8 · Medium

    What is the output of this code?

    items = ["pen", "ink", "nib"]
print(*items, sep=", ")
print(items)
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    Answer: A

    *items unpacks the list into three separate arguments, so sep is placed between them. The second print receives the list itself and shows it with brackets and quotes.

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  9. Question 9 · Hard

    What is the output of this code?

    name = "Asha"
score = 7
print(f"{name=}, {score * 2 = }")
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    Answer: B

    A trailing = in an f-string field prints the expression text and then its value using repr(), so the string keeps its quotes. Spaces around the = are kept exactly as written, which is why the second field shows score * 2 = 14.

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  10. Question 10 · Hard

    What is the output of this code?

    print(round(2.5), round(3.5), round(-0.5))
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    Answer: C

    round() with no digits argument sends an exact half to the nearest even integer (banker's rounding): 2.5 becomes 2, 3.5 becomes 4 and -0.5 becomes 0. Halves are not always rounded up.

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  11. Question 11 · Medium

    What is the output of this code?

    a = b = [1, 2]
b.append(3)
print(a)
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    Answer: A

    Chained assignment binds both names to the same list object; it does not make a copy. Appending through b changes that one list, so a shows the 3 as well.

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  12. Question 12 · Hard

    What is the output of this code?

    print(True + True * 3)
print(int("101", 2) + int(True))
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    Answer: D

    bool is a subclass of int, so True counts as 1, and * runs before +: 1 + 3 = 4. int("101", 2) reads the text in base 2, which is 5, and int(True) is 1, giving 6.

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  13. Question 13 · Easy

    Which error does this code raise?

    age = 16
print("Age: " + age)
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    Answer: C, TypeError: can only concatenate str (not "int") to str

    + cannot join a str and an int, so Python raises TypeError. Write "Age: " + str(age), use an f-string, or pass both values to print separated by a comma.

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  14. Question 14 · Medium

    Which error does this code raise?

    value = int("3.5")
print(value)
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    Answer: B, ValueError: invalid literal for int() with base 10: '3.5'

    int() accepts a string only if it looks like a whole number. "3.5" has a decimal point, so it raises ValueError instead of truncating. int(float("3.5")) gives 3.

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  15. Question 15 · Medium

    Which error does this code raise?

    2nd_place = "Ravi"
print(2nd_place)
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    Answer: A, SyntaxError: invalid decimal literal

    A variable name cannot start with a digit, so the program is rejected before any line runs. Python reports a SyntaxError, not a NameError, because 2nd_place is not a valid name at all.

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  16. Question 16 · Easy

    A program runs age = input("Age: ") and the user types 25. What is the type of age?

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    Answer: D, str

    input() always returns a string, whatever the user types. Convert it with int(age) before doing arithmetic with it.

  17. Question 17 · Easy

    Which of these is a valid Python variable name?

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    Answer: B, _score2

    Names may contain letters, digits and underscores but cannot start with a digit, so _score2 is valid. my-score reads as a subtraction, and class is a reserved keyword.

  18. Question 18 · Medium

    Which of these built-in types is immutable, so its items cannot be changed after it is created?

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    Answer: C, tuple

    A tuple cannot be changed in place: assigning to t[0] raises TypeError. Lists, dicts and sets all have methods that change them, such as append, update and add.

  19. Question 19 · Medium

    Which line prints exactly 5 + 3 = 8?

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    Answer: D

    print puts a space between its arguments, and 5 + 3 is worked out before printing, giving 5 + 3 = 8. Joining str(5) + str(3) makes 53, and adding an int to a str raises TypeError.

  20. Question 20 · Hard

    Given pi = 3.14159, which line prints 3.14?

    Show the answer

    Answer: A

    .2f means two digits after the decimal point. .2 without the f means two significant digits, giving 3.1, and 2f sets a minimum width of 2 with the default six decimals, giving 3.141590.

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