I have table "Masterstu.dbf" having fields 1. Regno 2. Applno 3. Category 4. dob 5. Physics 6. chemistry 7. Biology.
The category fields having 6 types of category 1. GE 2. OBC 3. MBC 4. SC 5. EBC 6. BCM. I want to select whose students marks less than 50% marks for "GE" Category and less than 40 % of marks for other category like OBC MBC SC EBC BCM in aggregate in the prescibed subjects of Physics, Chemistry, Biology.

(Eg). Regno Applno Category dob Physics Chemistry Biology
10002 33256 GE 15/2/1993 185 190 200
10003 38596 MBC 25/4/1994 178 200 189
10004 33479 OBC 14/3/1994 199 185 175
10005 35826 SC 11/3/1993 075 070 080
10006 35828 GE 11/5/1993 075 080 080

The maximum marks for each subject is 200

How to write Query for above my question?

awaiting your valuable reply