How to carry out integer and decimal arithmetic operations in Laravel Controller

I am dealing with Intger value, Double(of type 2,3 and 4 decimal point precision).

I am getting integer and decimal values from database. I need to do some arithmetic for example:

#val1, val2, val3 and val4 coming from database
((((((val1 + (1 * val2)) * 12.1234) * val3) / 1234) * 1) + val4)

#actual operation looks like
((((((12.34 + (1 * 1.234)) * 12.1234) * 1.234) / 1234) * 1) + 12) 

$field1 (10.50) + 100.00 in controller, I get Object of class App\Catf could not be converted to int

via Murlidhar Fichadia