Coin Bank Issues in [Code C#]

Hello so what i want is when you collect coins in the round you just played it adds up in a menu scene where is the coin text so lets say u picked up 5 coins in one round and you want to play another round and you do it and you get 7 coins so i want that those 7 coins add up to those 5 coins if you understand me whaat im tring to say here is my code:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 
 public class GameManager : MonoBehaviour
 {
     public static GameManager instance = null;
 
     public GameObject scoreTextObject;
 
     int score;
     Text scoreText;
 
 
     void Awake()
     {
         if (instance == null)
             instance = this;
         else if (instance != null)
             Destroy(gameObject);
 
         scoreText = scoreTextObject.GetComponent<Text>();
         scoreText.text = " " + score.ToString();
     }
 
     public void Collect(int passedValue, GameObject passedObject)
     {
         passedObject.GetComponent<Renderer> ().enabled = false;
         passedObject.GetComponent<Collider>().enabled = false;
         Destroy(passedObject, 1.0f);
 
         if (PlayerPrefs.GetFloat(" ") + score)
         PlayerPrefs.SetFloat(" ", score);
 
         score = score + passedValue;
         scoreText.text = ": " + score.ToString();
         // update our score UI
     }
 }
 

So when i try to play it says: cannot implicitly convert float to bool In the line 33 it says + score what i meanth by that is that it adds up but for some reason it doesnt work Thank you all of you who respond!