Hard to say, there aren't really tracked averages out there for mixed breeds like there are for pure breds. Probably anywhere from 1 to 6 but could always be more depending. You would find out about that sort of thing duing your standard prenatal care for evaluation.
The first link goes over many of the pregnancy and whelping basics for you if you would like to or need to know and has a lot of detailed links for you and there is more information in the other links for you. The breed parent clubs for the respective breeds are the second and third links. Good Luck.
q3525724.html#a2810229
http://www.asc-cockerspaniel.org/index.php/breeders.html http://www.poodleclubofamerica.org/ q2722771.html#a3046267
q5762034.html#a2906893
http://home.comcast.net/~NoPuppyMillsVA/Poo-dogs___Designer_Mutts/poo-dogs___designer_mutts.html
http://www.learntobreed.com/mutts.html
http://www.wildheirlabradorrescue.org/readingroom/what-is-a-back-yard-breeder.php
http://members.tripod.com/antique_fcr/goodbreeder.html
http://www.wonderpuppy.net/1breeding.php
http://www.petfinder.com/index.html
The first link goes over many of the pregnancy and whelping basics for you if you would like to or need to know and has a lot of detailed links for you and there is more information in the other links for you. The breed parent clubs for the respective breeds are the second and third links. Good Luck.
q3525724.html#a2810229
http://www.asc-cockerspaniel.org/index.php/breeders.html http://www.poodleclubofamerica.org/ q2722771.html#a3046267
q5762034.html#a2906893
http://home.comcast.net/~NoPuppyMillsVA/Poo-dogs___Designer_Mutts/poo-dogs___designer_mutts.html
http://www.learntobreed.com/mutts.html
http://www.wildheirlabradorrescue.org/readingroom/what-is-a-back-yard-breeder.php
http://members.tripod.com/antique_fcr/goodbreeder.html
http://www.wonderpuppy.net/1breeding.php
http://www.petfinder.com/index.html