[B]<form id="form" name="form" method="post" action="">

<select name="deger1" onChange="document.form.deger2.value =document.form.deger2.value+ this.value">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
</select>

<select name="deger2">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
</select>
</form>[/B]