You want to sum values from an array where some elements are strings with numbers and others are booleans. Which PHP code correctly sums all values?

hard📝 Application Q8 of 15

PHP - Type Handling

$arr = ['4', true, '3 cats', false];

A$sum = 0; foreach ($arr as $v) { $sum += (bool)$v; } echo $sum;

B$sum = 0; foreach ($arr as $v) { $sum .= $v; } echo $sum;

C$sum = 0; foreach ($arr as $v) { $sum += $v; } echo $sum;

D$sum = 0; foreach ($arr as $v) { $sum .= (string)$v; } echo $sum;

Step-by-Step Solution

Solution:

Step 1: Understand implicit type coercion in addition
Using '+=' with mixed types converts values to numbers automatically.
Step 2: Check each option
A sums correctly using implicit conversion ('4'->4, true->1, '3 cats'->3, false->0 =8). B concatenates strings. C casts to bool (1+1+1+0=3 wrong). D concatenates after string cast. Only A works.
Final Answer:
$sum = 0; foreach ($arr as $v) { $sum += $v; } echo $sum; -> Option C
Quick Check:
Use '+=' for numeric sum with mixed types [OK]

Quick Trick: '+=' auto-converts mixed types to numbers in PHP [OK]

Common Mistakes:

Master "Type Handling" in PHP

9 interactive learning modes - each teaches the same concept differently

Want More Practice?

15+ quiz questions · All difficulty levels · Free

More PHP Quizzes