X+(211+317)=778

To solve the equation \( x + (211 + 317) = 778 \), first compute the sum inside the parentheses:

\[ 211 + 317 = 528 \]

Now substitute this back into the equation:

\[ x + 528 = 778 \]

Next, isolate \( x \) by subtracting 528 from both sides of the equation:

\[ x = 778 - 528 \]

Calculating the right side gives:

\[ x = 250 \]

So, the solution is:

\[ \boxed{250} \]