Object of class stdClass could not be converted to int

[eluser]The Revel[/eluser]
Forgot the very first line of everything, how I get $total:

Code:

$total = (($this->input->post('qty1') * $this->input->post('pr1')) + ($this->input->post('qty2') * $this->input->post('pr2')) + ($this->input->post('qty3') * $this->input->post('pr3')) + ($this->input->post('qty4') * $this->input->post('pr4') + ($this->input->post('qty5') * $this->input->post('pr5')) + ($this->input->post('qty6') * $this->input->post('pr6')))) * -1 ;