Check Multiplications

<button onclick="Calc()">Start</button><br />
<input id="O1" size="1" value="" />x<input id="O2" size="1" value="" />=<input id="I" size="1" /><br />
<button onclick="Check()">Check</button><br />
<input id="Output3" size="3" value="" />
<script type="text/javascript">
function Calc()
  {var a,b,c;
   a=Math.floor(Math.random()*9)+1;
   b=Math.floor(Math.random()*9)+1;
   document.getElementById("O1").value=a; 
   document.getElementById("O2").value=b; 
}
  
function Check()
  {var x,y,z;
   x=Number(document.getElementById("O1").value);
   y=Number(document.getElementById("O2").value);
   z=Number(document.getElementById("I").value);
   if(x*y==z)document.getElementById("Output3").value="Correct";
   else document.getElementById("Output3").value="Wrong";
}
</script> 
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