Using a foreach variable in a Laravel view

My MySQL table looks like this (the relevant part):

student_id (int) | engmins(int) | totalmins(int) | created_at (datetime)    
1                | 50           | 100            | 2017-12-15 00:00:00
1                | 20           | 45             | 2017-12-15 00:00:00

I have the following code:

$students = StudentDetails::with('student','studentschool','classactivity')
    ->where('class', 1)
    ->orderBy('studentgrade', 'DESC')
    ->get();

$calculatePercentage = array();

foreach ($students as $s) 
{
    $fetchEngClassPercents= DB::table('ClassActivity')
    ->select(DB::raw('round((sum(engmins) * 60) / (sum(totalmins) * 60) * 100) as percents'))
    ->where('created_at', '>=', Carbon::now()->subDays(30))
    ->where('student_id', '=', $s->student->id)->get();     
    foreach($fetchEngClassPercents as $f)
    {
        $calculatePercentage = $f->percents;
        var_dump($calculatePercentage); //Debug purposes
    }
}

var_dump($calculatePercentage);  //Debug purposes

$params = [
    'engClassPercentage' => $calculatePercentage,
    'studentInfo'        => $students,
];

return view('user.classes.engclass.index', $params);

var_dump INSIDE the loop executes string(2) "43" NULL

var_dump OUTSIDE the loop executes NULL

This is how it looks in the view:

<td>
    @foreach($engClassPercentage as $p)
        {{ $p->percents }}
    @endforeach
</td>

This doesn't work in the view, it simply shows nothing.

For some reason, $calculatePercentage remains null outside of the loop (upon previous attempt of dumping the var). When it's in the foreach loop, it executes the query.

The strange thing is that I declared the array ($calculatePercentage) outside of the loop are assigned it with the variable in the foreach loop.

I am quite lost at this point to be honest, and I'd be glad if I can get assistance.

---

change $calculatePercentage = $f-percents; to like below. Then in foreach part change $p->percents to $p.

$calculatePercentage[] = $f->percents;

@foreach($engClassPercentage as $p)
   {{$p}}
@endforeach

---

$calculatePercentage is getting overwritten on each loop change it to an array key

$calculatePercentage[] = $f->percents;

Then in your foreach call the $params array

@foreach($params['engClassPercentage'] as $p)

---

You aren't storing values that is getting calculated in foreach loop:

Hence the values doesn't persist as per your requirements.

Updated Code:

foreach ($students as $s) 
{
    $fetchEngClassPercents= DB::table('ClassActivity')
    ->select(DB::raw('round((sum(engmins) * 60) / (sum(totalmins) * 60) * 100) as percents'))
    ->where('created_at', '>=', Carbon::now()->subDays(30))
    ->where('student_id', '=', $s->student->id)->get();     
    foreach($fetchEngClassPercents as $f)
    {
        $calculatePercentage[] = $f->percents; // <-- This line is edited.
    }
}

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