diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 6f5ecc7711b..bba253bcaf8 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -11369,7 +11369,7 @@ function isVisibleToUserType($type_user, &$menuentry, &$listofmodulesforexternal
  */
 function roundUpToNextMultiple($n, $x = 5)
 {
-	$result = (ceil($n) % $x === 0) ? ceil($n) : round(($n + $x / 2) / $x) * $x;
+	$result = (ceil($n) % $x === 0) ? ceil($n) : (round(($n + $x / 2) / $x) * $x);
 	return (int) $result;
 }
 
diff --git a/test/phpunit/FunctionsLibTest.php b/test/phpunit/FunctionsLibTest.php
index ce34604cc32..b28e945e28d 100644
--- a/test/phpunit/FunctionsLibTest.php
+++ b/test/phpunit/FunctionsLibTest.php
@@ -1797,4 +1797,29 @@ class FunctionsLibTest extends PHPUnit\Framework\TestCase
 
 		return true;
 	}
+
+
+	/**
+	 * testRoundUpToNextMultiple
+	 *
+	 * @return void;
+	 */
+	public function testRoundUpToNextMultiple()
+	{
+		$this->assertEquals(roundUpToNextMultiple(39.5), 40);
+		$this->assertEquals(roundUpToNextMultiple(40), 40);
+		$this->assertEquals(roundUpToNextMultiple(40.4), 45);
+		$this->assertEquals(roundUpToNextMultiple(40.5), 45);
+		$this->assertEquals(roundUpToNextMultiple(44.5), 45);
+
+		$this->assertEquals(roundUpToNextMultiple(39.5, 10), 40);
+		$this->assertEquals(roundUpToNextMultiple(40, 10), 40);
+		$this->assertEquals(roundUpToNextMultiple(40.5, 10), 50);
+		$this->assertEquals(roundUpToNextMultiple(44.5, 10), 50);
+
+		$this->assertEquals(roundUpToNextMultiple(39.5, 6), 42);
+		$this->assertEquals(roundUpToNextMultiple(40, 6), 42);
+		$this->assertEquals(roundUpToNextMultiple(40.5, 6), 42);
+		$this->assertEquals(roundUpToNextMultiple(44.5, 6), 48);
+	}
 }