A hypo lavender x an amel stripe would give you all normals het for amel, hypo, lavender, and stripe (assuming that neither parent is carrying any hets).
Breeding the offspring together would be expected to give you the following phenotypes (each of which has a 67% chance of being het for the remaining traits that it isn't expressing):
81/256 Normals
36/256 Amels (9 of 36 also being homo for Hypomelanism)
27/256 Hypos
27/256 Striped
27/256 Lavs
9/256 Hypo Striped
12/256 Amel Striped (3 of 12 also being homo for Hypo)
9/256 Lav Striped
9/256 Hypo Lavs
12/256 Opals (amel lav) (3 of the 12 also being homo for Hypo)
4/256 Striped Opal (1 of the 4 also being homo for Hypo)
3/256 Striped Hypo Lav
If you breed one of the offspring back to the hypo lav, you'd be expected to get:
1/4 Hypo Lavenders (50% het amel, 50% het stripe)
1/4 Lavenders het for hypo (50% het amel, 50% het stripe)
1/4 Hypos het lavender (50% het amel, 50% het stripe)
1/4 Normals het hypo lav (50% het amel, 50% het stripe)
If you breed one of the offspring back to the Amel Striped, the ratios would be the same, just different traits:
(all would have a 50% chance of being het lavender, 50% het hypo)
1/4 Amel Stripes
1/4 Amels het striped
1/4 Stripes het amel
1/4 Normals het amel and stripe
A great place to learn why these ratios are as they are is Serpwidgets's genetics tutorial. He goes into great detail to help you understand why these crosses turn out as they do.
Good luck!
