SOLUTION: 28,35,?,77 number in place of question mark

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Question 927690: 28,35,?,77 number in place of question mark
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
28, 35, highlight%2849%29 , 77

28=7%2A4
35=7%2A5
%22%3F%22=7%2A%22%3F%3F%22
77=7%2A11

so the new question is 4, 5, ?? , 11.
I decided that the person who invented the problem thought of
4, 5, 7, 11
because
4%2B1=5 or 4%2B2%5E0=5 ,
5%2B2=7 or 5%2B2%5E1=7 , and
7%2B4=11 or 7%2B2%5E2=11 ,
where you get the next term in the sequence by adding the next power of 2.