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<?php $testOne = array ( 'Smith'=> 98, 'Johnson' => 67, ); $testTwo = array ( 'Smith'=> 100, 'Johnson' => 85, ); $testThree = array ( 'Smith'=> 78, 'Johnson' => 92, ); $testFour = array ( 'Smith'=> 91, 'Johnson' => 88, ); $total = [$testOne, $testTwo, $testThree, $testFour]; Foreach($total[0] as $name => $val){ $averages[$name] = array_sum(array_column($total, $name))/count($total); } var_dump($averages);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(2) { ["Smith"]=> float(91.75) ["Johnson"]=> int(83) }

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