Heterozygous straight (F) x heterozygous bent (f)
________
|FF | Ff |
|Ff | ff |
That means 1/4 will be 100% straight
2/4 will have straight with a recessive trait of bent
1/4 will be recessive recessive which means bent
So out of 4 chimpanzees, 1 of them will have bent.
Hope this is what you wanted help with. :)