464. A number consists of three digits; the sum of these digits is 11; the digit in the units place is twice the digit in the hundreds place. If you add 297 to the desired number, you get a number written with the same digits as the desired number, but in reverse order. What number has these properties?
464. The question boils down to solving the system:

$$
\left\{\begin{array}{l}
x+y+z=11 \\
z=2 x \\
100 x+10 y+z+297=100 z+10 y+x
\end{array}\right.
$$

$x=3 ; y=2 ; z=6$. The desired number is 326.