The sum of the squares of three numbers is 225, while the sum of their products taken two at a time is 200. Their sum is:	Choose the correct answer:	A) 10	B) 30	C) 40	D) 25	E) None of these
x^+y^2+z^2=225   xy+yz+zx=200   as we know.. (x+y+z)^2=x^2+y^2+z^2+2(xy+yz+zx)   so (x+y+z)^2=225+(2*200)   (x+y+z)^2=625   so x+y+z=25   ANSWER:25
<result>D</result>
The sum of the squares of three numbers is 225, while the sum of their products taken two at a time is 200. Their sum is: