<html><head><center> <h1> Petrol Calculator</h1></center>
<script language =" javascript">
function writetext (form) { var KPL = form.inputbox.value; var Fuel = form.inputbox2.value; form.inputbox3.value =KPL * Fuel }
</script></head><body><form name = "myform">Enter Petrol Milage<br><input type = "text" name = "inputbox" value = ""><p><br>Enter Amount OF Fuel:<br><input type = "text" name = "inputbox2" value = ""><p><br>KiloMeters To Travel:<br><input type = "text" name = "inputbox3" value = ""><p><br>
<input type = "button" name = "button" value = "Display KM" onclick ="writetext(this.form)">
</body></html>