SELECT PM.PMNUM, (COUNT(ROUTE_STOP.LOCATION) * JOBPLAN.JPDURATION)
FROM PM
LEFT OUTER JOIN ROUTE_STOP ON ROUTE_STOP.ROUTE = PM.ROUTE
LEFT OUTER JOIN JOBPLAN ON JOBPLAN.JPNUM = PM.JPNUM
GROUP BY PM.PMNUM
SELECT PM.PMNUM, (COUNT(ROUTE_STOP.LOCATION) * JOBPLAN.JPDURATION)
FROM PM
LEFT OUTER JOIN ROUTE_STOP ON ROUTE_STOP.ROUTE = PM.ROUTE
LEFT OUTER JOIN JOBPLAN ON JOBPLAN.JPNUM = PM.JPNUM
GROUP BY PM.PMNUM, JOBPLAN.JPDURATION
If this won't help you need to give further feedback what is not working?
As I see your minimum missing a group by.
If this won't help you need to give further feedback what is not working?