5 9 12 18 26 36 47 72 a 75 b 135 c 100 d 55

9,18,36,72,..... - one series
5,12,26,47,75,....- one series.
5
5 + 7 = 12
12+ 7(2)= 26
26+ 7(3)= 47
.
.
..
11 years agoHelpfull: Yes(4) No(0)
answer is 75
the series is a mixture of 2 series, one with odd terms and other with even terms
so consider series 5,12,26,47,...
it has difference of 12-5=7,26-12=14,47-26=21,so next term will be 75-47=28
since the difference is increasing in multiple of 7
11 years agoHelpfull: Yes(1) No(0)
Punitha what about 9 in the sequence???
11 years agoHelpfull: Yes(0) No(0)
two series are here: 5 ,5+7,12+7*2,26+7*3,47+7*4=75
9,18,36,72
11 years agoHelpfull: Yes(0) No(0)
ans will be 75 ..
11 years agoHelpfull: Yes(0) No(0)
9,18,36,72 is another series which is multiplication of 2s.
Now we have to consider the first set only.
That is 5,12,26,47,--
In that place as i said earlier 75 will come
11 years agoHelpfull: Yes(0) No(1)
answer = a
5 years agoHelpfull: Yes(0) No(0)

5, 9, 12, 18, 26, 36, 47, 72, _?
a) 75
b) 135
c) 100
d) 55