Getting sum the from various tables and columns

[davykiash]

i have three queries below. when i run them they work fine. they return the values 100,200 and 300 respectively.However i would like to run a single query instead that will return 600. i tried using UNION to join them but i am getting all the 3 values as a recordset

Any ideas
i am using MySQL 4.1.7.

SELECT sum(consultation)+ sum(laboratory) FROM nairobi,familymembers WHERE
familymembers.dependantid = nairobi.memberid and familymembers.memberid = "AKI100000001"

SELECT sum(consultation)+ sum(laboratory) FROM rift,familymembers WHERE
familymembers.dependantid = rift.memberid and familymembers.memberid = "AKI100000001"

SELECT sum(consultation)+ sum(laboratory) FROM coast,familymembers
familymembers.dependantid = coast.memberid and familymembers.memberid = "AKI100000001"

Thanks