Question

What is the next number in the seires?
12 35 81 173 357 _______.

• A. 368

Answer 1

The correct option is A 368
12, 35, 81, 173, 357, _____

Difference between consecutive terms of the series are :
13, 46, 92, 184, ____

$35-12=23=23\times 1$
$81-35=46=23\times 2$
$173-81=92=23\times 4$
$357-173=185=23\times 8$

So the next difference have to be $23\times 8=368$,

therefore next term have to 357 + 368

$=725$
$=23\times 16$

$725-357=368=23\times 16$