function compute(form){
var vfin=0
var pini=0
var vini=0
var pfin=0

pfin=(eval(form.pini.value)*eval(form.vini.value)/eval(form.vfin.value))
form.pfin.value=pfin
form.edita.value="("+form.pini.value+"x"+form.vini.value+"/"+form.vfin.value+")"
}
function calc(form){
var vbfin=0
var pbini=0
var vbini=0
var pbfin=0

vbfin=(eval(form.pbini.value)*eval(form.vbini.value)/eval(form.pbfin.value))
form.vbfin.value=vbfin
form.editb.value="("+form.pbini.value+"x"+form.vbini.value+"/"+form.pbfin.value+")"
}
function clearForm(form){
form.pini.value="0";
form.vini.value="0";
form.vfin.value="0";
form.pfin.value="";
form.edita.value="";
form.pbini.value="0";
form.vbini.value="0";
form.pbfin.value="0";
form.vbfin.value="";
form.editb.value="";
}