Aggregate functions (Count, Sum, Average) in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to count the number of elements in the list.

C Sharp (C#)

int count = numbers.[1]();

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

ACount

BSum

CAverage

DMax

Attempts:

3 left

💡 Hint

Common Mistakes

Using Sum() instead of Count()

Using Average() which calculates the mean

Using Max() which finds the largest value

The Count() method returns the number of elements in the list.

2fill in blank

medium

Complete the code to calculate the sum of all elements in the list.

C Sharp (C#)

int total = numbers.[1]();

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

AMin

BSum

CAverage

DCount

Attempts:

3 left

💡 Hint

Common Mistakes

Using Count() which returns the number of elements

Using Average() which calculates the mean

Using Min() which finds the smallest value

The Sum() method adds all the numbers in the list together.

3fill in blank

hard

Fix the error in the code to calculate the average of the list elements.

C Sharp (C#)

double avg = numbers.[1]();

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

AAverage

BCount

CSum

DMax

Attempts:

3 left

💡 Hint

Common Mistakes

Using Sum() which adds all elements

Using Count() which counts elements

Using Max() which finds the largest element

The Average() method calculates the mean value of the list elements.

4fill in blank

hard

Fill both blanks to create a dictionary with words as keys and their lengths as values.

C Sharp (C#)

var lengths = new Dictionary<string, int> { { [1], [2] } };

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Aword

Bword.Length

Cword.Length > 3

D"length"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a boolean expression as a value

Using a string 'length' instead of the actual length

Using the length as key instead of value

Use the word itself as the key and its length as the value.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase words to their lengths, including only words longer than 4 characters.

C Sharp (C#)

var result = words.Where(word => word.Length [1] 4).ToDictionary([2] => [3], word => word.Length);

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A>

Bw

Cw.ToUpper()

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' in the filter

Using the original word as key instead of uppercase

Using the wrong lambda parameter name

Filter words longer than 4, then map each word's uppercase form as key and length as value.