javascript - How to display calculated values in IE9 -

i'm working on online form attendees of conference fill out. each person enters amount of minutes attended session. minutes convert credit hours in form field so:

<div class="col3">   <form onsubmit="return false" oninput="document.getelementbyid('mk1').innerhtml = (math.floor((mc06.value/50) * 2) / 2).tofixed(1)">     <input name="mc06" id="mc06" onkeyup="disablefield06()" type="number" min="0" max="50" placeholder="0-75 minutes" step="any" /> </div> <div class="col1">   <output name="mk1" id="mk1">0</output>   </form> </div> 

in case you're wondering, disablefield function disables session same time slot. no problems there. no problems placeholder either, script found here.

the hours subject category (mk in case) collected in function when user clicks submit button:

var mk1 = document.getelementbyid("mk1").value; var mk2 = document.getelementbyid("mk2").value; var mk3 = document.getelementbyid("mk3").value; var mk4 = document.getelementbyid("mk4").value; var mk5 = document.getelementbyid("mk5").value; var mk6 = document.getelementbyid("mk6").value; document.getelementbyid("mk").value = parsefloat(mk1) + parsefloat(mk2) + parsefloat(mk3) + parsefloat(mk4) + parsefloat(mk5) + parsefloat(mk6); 

finally, subjects , total hours per attendant displayed in table @ bottom.

      <div class="table-row">           <div class="col2">marketing:  </div>           <div class="col4"><input type = "text" id = "mk" name = "mk"></div>       </div> 

this works fine in chrome, in ie9 (the company browser) nan. how can fix this?

i fixed it.

i changed code lines like

var mk1 = document.getelementbyid("mk1").value; 

to

var mk1 = document.getelementbyid("mk1").innerhtml; 

that worked data called input fields. code totals subjects' credit hours still returned nan. changed lines .value, , worked! looks ie9 has narrower scope .value other browsers.