Please, could anybody explain for me?
In the box of Revell's Battleship HMS King George V, kit #05016, the scale is 1/720, and her size is 40cm.
But in the box of Revell's Battleship HMS Prince Wales, kit #05017 the scale is 1/570, and her size is 39,7cm.
The price is also different, around US$41,00 for the first one and US$13.00 for the other.

They are both 720 scale. Can't figure the price diference. One may be full hull with photoetched. I'ld say if you can't actually look at both kits, buy the cheaper version

Other way round, they're both 1/570 or so.

I bought the PoW recently and it's the model I remember from the 70s, bit rough now due to mould wear and some sinkmarks where the locations for the gun tubs of the KGV model are covered over.

Bingo!
Thank you guys, but I think I found the mistake, it is in the indication of the scale of HMS King George V kit, because, according “Ships of the World: An Historical Encyclopedia”
The ships were 227,1m longer. Then, the correct scale for both, if I am not wrong, is 1/570. Regarding the prices, I don’t know why the difference.
I also did not read anything about that, yet.
Thank you again,
Cheers,

oops, long

If you haven't bought yet, let me advise you on something better. Check on ebay and you can get the wonderful Tamiya 350 scale version of one of these for around $40 maybe even less. If that is too big, Tamiya also does a 700 scale waterline version that seems to be going for around $13-15 on ebay. There are phototetched sets available for both versions that really add to it. I picked up the 350 scale KGV a couple of years ago for around $30 added a Tom's Pe set to it and it stands proud alongside my other 350 scale ships.

Thank you Steve, but I found both kits at the same price, here. That’s why I was asking about the difference. I already started the negotiation with the kits’ owner.
1/350 is a good size, I like it. 1/700 I like only carriers.
I’ll see the E-bay offers, perhaps I’ll find a good one.
Cheers