Insert the missing number.

7, 26, 63, 124, 215, 342, (....)

A.
481
B.
511
C.
391
D.
421

• 511
  
  all terms are of series (n+1)^3 -1
  so (7+1)^3-1 = 512-1 =511 .. option B
• 12 years agoHelpfull: Yes(22) No(1)
• option......D
  see sum of the digits.it follows a sequence as 7,8,9,7,8,9,.....,
  so reqiured answer should have sum of digits of a number=7
• 12 years agoHelpfull: Yes(7) No(17)
• 2^3-1=7
  3^3-1=26
  4^3-1=63
  5^3-1=124
  6^3-1=215
  7^3-1=342
  8^3-1=511
  
  so answer is=B=511
• 9 years agoHelpfull: Yes(3) No(0)