calculate a percentage into a decimal? (HP-Bar)

hey gang! I have calculated my Player HP into 100 %. I'm trying to translate this into decimals so 100% = 1 80% = 0.8 act So i can use this number in Imagefill for a HP bar since Fillamount Only likes decimals :D

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 public class PlayerHealth : MonoBehaviour {
 
     public float playerhealth;
     public float MaximumPlayerHealth;
     public float PlayerHealthPersentage;
     public float PlayerFloatDecimal;
 
     public Image PlayerHP; 
     public IndavidualScore Score;
     public GameObject Missioncontroll;
 
     public void Start (){
 
     }
 
     public void LateUpdate (){
 
         // Calculate HP get 100%
         PlayerHealthPersentage = playerhealth / MaximumPlayerHealth * 100;
         //????????????????????_______________________________________________
         //Set 100% to a decimal 100 = 1 80 = 0.8 act.....
           = PlayerFloatDecimal;   //????????????????????
         //????????????????????_______________________________________________
 
         if (Missioncontroll == null) {
             Missioncontroll = GameObject.FindGameObjectWithTag("MissionControll");
             Score = Missioncontroll.GetComponent<IndavidualScore> ();
         }
 
         PlayerHP.fillAmount = PlayerFloatDecimal; //Display HP BAR XD    
 
         if(playerhealth < 1){
             Score.Lives -= 1;
         }
     }
 
 
 }