What number is half way between 170,000 and 180,000?

Like Kenzie said, it's 175,000. Now, to get it you only need to get both numbers' average:

First add 170000+180000, and then divide it by 2 (because you added 2 numbers in total).

So 170,000+180,000 = 350,000

And then 350,000/2 = 175,000