Why lists hold mixed types in R Programming - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a list with mixed types.

R Programming

my_list <- list(1, "apple", [1], TRUE)

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A3.14

Blist()

Cc(1,2,3)

DNULL

Attempts:

3 left

💡 Hint

Common Mistakes

Using a vector like c(1,2,3) instead of a single value.

Using list() which creates an empty list inside the list.

The list can hold different types like numbers, strings, and logical values. Here, 3.14 is a numeric value added to the list.

2fill in blank

medium

Complete the code to access the second element of the list.

R Programming

second_element <- my_list[1]2

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A%%

B[

C$

D[[

Attempts:

3 left

💡 Hint

Common Mistakes

Using single brackets which return a list, not the element.

Using $ which works only with named elements.

In R, double square brackets [[ ]] are used to extract elements from a list by position.

3fill in blank

hard

Fix the error in the code to add a new element to the list.

R Programming

my_list[1] <- 42

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A[["5"]]

B[5]

C[[5]]

D$5

Attempts:

3 left

💡 Hint

Common Mistakes

Using single brackets which assign a sublist, not an element.

Using $ with a number which is invalid.

To add a new element at position 5, use double square brackets with the index [[5]].

4fill in blank

hard

Fill both blanks to create a list with a numeric and a character element.

R Programming

my_list <- list([1], [2])

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A10

B"hello"

CTRUE

Dc(1,2)

Attempts:

3 left

💡 Hint

Common Mistakes

Using a logical value TRUE instead of a number or string.

Using a vector c(1,2) which is not a single element.

The list holds a number 10 and a string "hello" as two different types.

5fill in blank

hard

Fill all three blanks to create a list and access its third element.

R Programming

my_list <- list([1], [2], [3])
third_element <- my_list[[3]]

Drag options to blanks, or click blank then click option'

A"apple"

B3.14

CTRUE

D42

Attempts:

3 left

💡 Hint

Common Mistakes

Using logical TRUE instead of a number for the third element.

Mixing up the order of elements.

The list contains a string "apple", a number 3.14, and a number 42. The third element is accessed with [[3]].