num1 is the first number
"; echo "$this->num2 is the second number
"; } } class addCalc extends baseCalc { function calculate() { var $num3 = $num1 + $num2; echo "$this->num1 plus $this->num2 equals $this->num3
"; } } class subCalc extends baseCalc { function calculate() { var $num3 = $num1 - $num2; echo "$this->num1 minus $this->num2 equals $this->num3
"; } } class mulCalc extends baseCalc { function calculate() { var $num3 = $num1 * $num2; echo "$this->num1 times $this->num2 equals $this->num3
"; } } class divCalc extends baseCalc { function calculate() { var $num3 = $num1 / $num2; echo "$this->num1 divided by $this->num2 equals $this->num3
"; } } $object1 = new baseCalc(); $object1 -> calculate(); $object2 = new addCalc(); $object2 -> calculate(); ?>