The regulation here seems to be 14 CFR 61.57(c)(1). The way that the regulation is written, we can see that there are three separate requirements:
(1) Use of an airplane, powered-lift, helicopter, or airship for maintaining instrument experience. Within the 6 calendar months preceding the month of the flight, that person performed and logged at least the following tasks and iterations in an airplane, powered-lift, helicopter, or airship, as appropriate, for the instrument rating privileges to be maintained in actual weather conditions, or under simulated conditions using a view-limiting device that involves having performed the following -
(i) Six instrument approaches.
(ii) Holding procedures and tasks.
(iii) Intercepting and tracking courses through the use of navigational electronic systems.
So it's not "a combination of the above that total 6", and it's not 6 of each. It's 6 of the first one, and any amount of both of the other two.