Calculating Class Duration in hours * Number of Participants

Participants * hours

In a Laravel project, I have a “Training” model that stores training class information. Here are the fields:
```
id title startdt
enddt
duration
totaltime shiftcode
shift
stationcode station
unitcode
unit
location
catid
methodid description created_at updated_at

There is a related pivot table name “training_participants” that matches the participants to a training record.  Here are the fields in the training record.
```
training_id 
user_id 
notes 
created_at 
updated_at 

My Training Model looks like this:

```
<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory; use Illuminate\Database\Eloquent\Model; use Spatie\MediaLibrary\MediaCollections\Models\Media; use Spatie\MediaLibrary\HasMedia; use Spatie\MediaLibrary\InteractsWithMedia;

class Training extends Model implements HasMedia {

use HasFactory;
use InteractsWithMedia;

// Overwrite the Default Name of the database table
protected $table = 'training';


protected $fillable = [
    'user_id',
    'title',

    'startdt',
    'enddt',
    'duration',
    'totaltime',
    'shiftcode',
    'shift',
    'stationcode',
    'station',
    'unitcode',
    'unit',
    'location',
    'catid',
    'methodid',
    'skills',
    'courseid_internal',
    'courseid_state',
    'courseid_national',
    'location_type',
    'addr_number',
    'addr_street',
    'addr_city',
    'addr_county',
    'addr_state',
    'addr_postalcode',
    'addr_lat',
    'addr_lng',
    'description'
];


public function user()
{
    return $this->belongsTo(User::class);
}

public function category()
{
    return $this->belongsTo(Category::class, 'catid', 'id');
}

public function trainingMethod()
{
    return $this->belongsTo(Category::class, 'methodid', 'id');
}

public function participants()
{
    return $this->belongsToMany(User::class, 'training_participants');
}

public function participantsCount()
{
    return $this->belongsToMany(User::class, 'training_participants')
        ->selectRaw('count(*) as count')
        ->groupBy('training_id');
}

public function instructors()
{
    return $this->belongsToMany(User::class, 'training_instructors');
}

}


```

I need help developing a method/function for my TrainingController that calculates the number of participants for all classes within a specified date range multiplied by the Duration of each class with the same date range. The date range can be accessed by the $range_startdt and $range_enddt variables in the function. The calculated number of hours should be returned as $ReportStaffHours .