I'm figuring it may be too late, which I am very sorry about if so, but the answer is 470.
You multiply the base times the height, which is 650 times 450, and get 292,500.
Next, you multiply 25 times 25 and get 625.
And lastly, you divide both 292,500 and 625 to get 468 which would approximately sum up to be 470.
Hope this helped =)