Ridiculously simple JS calculation problem

[Russinating]

I'm just trying to do a simple JS addition, but it's treating one of the vars as a string and I don't know to adjust this.

var baseprice = 12;
var packaging = document.getElementById("packaging");
totalprice = baseprice + packaging.value;
document.getElementById("totalprice").innerHTML = "£" + totalprice + ".00"

If packaging.value is 3 then it outputs 123. If I replace the + with a - or * then it works fine (ie outputs 9 and 36 respectively).

This is probably so simple that I doubt I need to explain any more, but it's doing my nut in. Cheers.

 

[GravyMonster]

the packaging.value is being interpreted as a string. If you explicitly state that packaging.value is an integer you'll fix the problem:

totalprice = baseprice + parseFloat(packaging.value);

 

[Russinating]

Perfect, cheers .