Why loops are needed in PHP - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to print numbers from 1 to 5 using a loop.

PHP

<?php
for ($i = 1; $i [1] 5; $i++) {
    echo $i . "\n";
}
?>

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

A<

B>

C>=

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < will only print 1 to 4.

Using > or >= will not run the loop correctly.

The loop should run while $i is less than or equal to 5, so using <= with 5 makes it print 1 to 5.

2fill in blank

medium

Complete the code to sum numbers from 1 to 10 using a loop.

PHP

<?php
$sum = 0;
for ($num = 1; $num [1] 10; $num++) {
    $sum += $num;
}
echo $sum;
?>

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

A<=

B<

C>

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < will exclude 10 from the sum.

Using > or >= will not run the loop correctly.

Using <= ensures the loop includes 10 in the sum.

3fill in blank

hard

Fix the error in the loop condition to print even numbers from 2 to 10.

PHP

<?php
for ($i = 2; $i [1] 10; $i += 2) {
    echo $i . "\n";
}
?>

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

A>

B<

C<=

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < excludes 10 from the output.

Using > or >= will cause the loop not to run.

Using <= includes 10 in the output, so even numbers 2,4,6,8,10 are printed.

4fill in blank

hard

Fill both blanks to create an associative array of squares for numbers 1 to 5.

PHP

<?php
$squares = [];
for ($i = 1; $i <= 5; $i++) {
    $squares[[1]] = [2];
}
print_r($squares);
?>

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

A$i

B$i * $i

C$i + 1

D$i - 1

Attempts:

3 left

💡 Hint

Common Mistakes

Using $i + 1 or $i - 1 will give wrong keys or values.

Swapping keys and values causes incorrect array.

The key should be $i and the value should be $i * $i to store squares.

5fill in blank

hard

Fill all three blanks to create a filtered array of numbers greater than 3 with their squares.

PHP

<?php
$numbers = [1, 2, 3, 4, 5];
$result = [];
foreach ($numbers as [1]) {
    if ([1] > 3) {
        $result[[2]] = [3];
    }
}
print_r($result);
?>

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

A$num

B$num * $num

D$number

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names causes errors.

Not filtering numbers greater than 3.

Use $num as the key and $num * $num as the value for numbers greater than 3. The loop variable is $num.