Multiple choice general knowledge math & puzzles 23,45,89,177,___ 345 353 386 293 Reveal answer Fill a bubble to check yourself B Correct answer Explanation The pattern is (n * 2) - 1, (n * 2) - 1... no. The pattern is: 23*2 - 1 = 45; 45*2 - 1 = 89; 89*2 - 1 = 177; 177*2 - 1 = 353. Each subsequent number is double the previous number minus one.