我如何使用for循环来获得添加结果？ [关闭]

Question

My math query is (1+5+ 10+15+20+25 =?)

How I use for loop to get the addition result?

Answer 1

  $answer = 1;

  for($x=1;$x<6;$x++){
      $answer+=5*$x;
  }

  echo $answer;