Fixed the example for Chain of Responsibility (kamranahmedse#49)

Now it will actual give the same result as the example snippet before it was just returning:
Paid 259 using Bank

README.md

@@ -1156,7 +1156,7 @@ abstract class Account {
 
     public function pay(float $amountToPay) {
         if ($this->canPay($amountToPay)) {
-            echo sprintf('Paid %s using %s' . PHP_EOL, $amount, get_called_class());
+            echo sprintf('Paid %s using %s' . PHP_EOL, $amountToPay, get_called_class());
         } else if ($this->successor) {
             echo sprintf('Cannot pay using %s. Proceeding ..' . PHP_EOL, get_called_class());
             $this->successor->pay($amountToPay);
@@ -1166,31 +1166,31 @@ abstract class Account {
     }
 
     public function canPay($amount) : bool {
-        return $this->balance <= $amount;
+        return $this->balance >= $amount;
     }
 }
 
 class Bank extends Account {
     protected $balance;
 
     public function __construct(float $balance) {
-        $this->$balance = $balance;
+        $this->balance = $balance;
     }
 }
 
 class Paypal extends Account {
     protected $balance;
 
     public function __construct(float $balance) {
-        $this->$balance = $balance;
+        $this->balance = $balance;
     }
 }
 
 class Bitcoin extends Account {
     protected $balance;
 
     public function __construct(float $balance) {
-        $this->$balance = $balance;
+        $this->balance = $balance;
     }
 }
 ```