How big will my dog get?

My dog is a mix of Greyhound and Chihuahua (but the shelter wasn't sure). Its hand is bigger than a Chihuahua's, like medium sized but not big like the big dogs paws when they're puppies. But if it was a mix of Chihuahua/Greyhound, what are the chances that it will be Greyhound size vs Chihuahua sized?It's definitely Greyhound but the Chihuahua part is what they're unsure about

The Greyhound will probably be dominant, or it'll be in between.Greyhounds should get 60-70lbs, I would guess 30-40lbs, roughly.