answering my own question here...
secs=$(print $elapsed | cut -c5-6)
where $elapsed might = "14:21:36"
at this point, secs="36"
and temp=$(( $secs * 60 )) won't work.
if first invocation of secs is preceded by,
integer secs
shell converts(?) it to a number when assigned.
Well, whatever it does, it now works in shell arithmetic.