Directions for Questions 46 - 50: What will come at the place of question mark (?) in the following number series?
11, 31, ?, 131, 223, 351
64
69
75
54
68
Solution
$2^3 + 3 = 11$
$3^3 + 4 = 31$
$4^3 + 5 = 69$
$5^3 + 6 = 131$
$6^3 + 7 = 223$
$7^3 + 8 = 351$