Which number will replace the question mark (?) in the following series?
11, 30, 68, 144, 296, ?

Let's look at the relation between consecutive numbers:
11×2+8=22+8=30

30×2+8=60+8=68

68×2+8=136+8=144

144×2+8=288+8=296

The common multiplier rule is (Current term×2)+8.

Applying this rule to find the missing next term:

296×2+8=592+8=600