Type coercion in operations in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a string number and an integer.

PHP

<?php
$result = '5' [1] 3;
echo $result;
?>

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

A+

B.

C-

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using the dot operator (.) which concatenates strings instead of adding numbers.

Using + causes PHP to convert the string '5' to the number 5 and then add 3, resulting in 8.

2fill in blank

medium

Complete the code to concatenate a string and a number.

PHP

<?php
$result = 'Value: ' [1] 10;
echo $result;
?>

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

A*

B+

C-

D.

Attempts:

3 left

💡 Hint

Common Mistakes

Using plus (+) which tries to add and converts the string to zero.

The dot operator . concatenates strings in PHP, so 'Value: ' and 10 become 'Value: 10'.

3fill in blank

hard

Fix the error in the code to correctly multiply a string number by an integer.

PHP

<?php
$result = '4' [1] 2;
echo $result;
?>

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

A.

B*

C-

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using the dot operator (.) which causes a string concatenation instead of multiplication.

The multiplication operator * converts the string '4' to number 4 and multiplies by 2, resulting in 8.

4fill in blank

hard

Fill both blanks to create an array where keys are string lengths and values are the strings themselves, only for strings longer than 3 characters.

PHP

<?php
$words = ['apple', 'cat', 'banana', 'dog'];
$result = array_combine(array_map('strlen', array_filter($words, function($word) {
    return strlen($word) [1] 3;
})), array_filter($words, function($word) {
    return strlen($word) [2] 3;
}));
print_r($result);
?>

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

A>

B<

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < or == which would select wrong words or none.

The condition strlen($word) > 3 filters words longer than 3 characters. array_map('strlen', filtered_words) gets lengths as keys for the filtered strings.

5fill in blank

hard

Fill both blanks to create a dictionary with uppercase keys, original values, and only include values greater than 10.

PHP

<?php
$data = ['a' => 5, 'b' => 15, 'c' => 20];
$result = array_filter(array_combine(array_map('[1]', array_keys($data)), $data), function($value) {
    return $value [2] 10;
});
print_r($result);
?>

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

Astrtoupper

B>

C>=

Dstrtolower

Attempts:

3 left

💡 Hint

Common Mistakes

Using strtolower instead of strtoupper.

Using >= instead of > changes the filter condition.

Using strtoupper converts keys to uppercase. The filter keeps values greater than 10 with >.