JSFiddle - React, Tailwind, and code Playground

HTML

<div id="powermsg">Hi</div>
<a href="javascript:;" onclick="javascript: changePowerMsg(200);">Change!</a>

JavaScript

function getPowerMsg(kj){
		var kwh = kj * 0.00027777777777778;
		var stuff = [["an LED night light", 0.5],["a clock radio", 4],["a night light", 5]];
		
		for(var i=0; i<stuff.length; i++){
			item = stuff[i][0];
			watts = stuff[i][1];
			kwatts = watts/1000;
			hours = (Math.floor((kwh/kwatts)*2)/2);
			if(hours > 0){
				results.push([item, convertTime(hours)]);
			}
		}
	    return results[randbetween(0,results.length-1)];
}

function convertTime(hrs){
		var msg = "";
		if(hrs < 24){
			msg = hrs+" hour";
			if(hrs != 1){ msg += "s"; }
			if(hrs < 1){ msg = "a half hour"; }
		}else if(hrs == 24){
			msg = "a full day";
		}else if(hrs < 33){
			msg = "over a day";
		}else if(hrs < 39){
			msg = "about a day and a half";
		}else if(hrs < 48){
			msg = "almost 2 days";
		}else if(hrs == 48){
			msg = "2 days";
		}else if(hrs < 60 ){
			msg = "over 2 days";
		}else if(hrs < 72){
			msg = "almost 3 days";
		}else if(hrs == 72){
			msg = "3 days";
		}else{
			msg = "over 3 days";
		}
		return msg;
}
	
function changePowerMsg(num){
	document.getElementById("powermsg").innerHTML = getPowerMsg(num);
}