Question Detail

8, 9, 8, 7, 10, 9, 6, 11, 10, (...), 12

Answer: Option C

Explanation:

Please note that above sequence is containing 3 series
Series 1 : 8, 7, 6, (..)
Series 2 : 9, 10, 11, 12
Series 3 : 8, 9, 10

In series 1 pattern is -1. So missing term will be 6-1 = 5

1. 13, 35, 57, 79, 911, ?

1005
1110
1113
1140

Answer: Option C

Explanation:

The terms of the given series are numbers formed by joining together consecutive odd numbers in order i.e. 1 and 3, 3 and 5, 5 and 7, 7 and 9, 9 and 11, .....

So, missing term = number formed by joining 11 and 13 = 1113.

2. 2,15,41,80, ? . Complete the series.

Answer: Option B

Explanation:

Pattern is +13,+(13*2), +(13*3)
Next will be +(13*4) = 80+52 = 132

3. Complete the series, 3, 8, 13, 24, 41, ?

Answer: Option A

Explanation:

Pattern of the above series is
first + second + 2, second + third + 3, third + fourth + 4......
So next term will be
24 + 41 + 5 = 70

4. In the series 2, 6, 18, 54, ... what will be the 8th term ?

4174
4150
4274
4374

Answer: Option D

Explanation:

We can see the given series is in G.P.
as 2*3 = 6, 6*3 = 18, 18*3 = 54
So a = 2 , r = 3
nth term in G.P. is
\begin{aligned}
ar^{n-1} \\
= 2*3{8-1} \\
= 2*3^7 \\
= 2*2187 = 4374
\end{aligned}

5. 20, 19, 17, (...) , 10, 5

Answer: Option D

Explanation:

Pattern in the series is -1, -2, .., .. , -5

So next term will be 17 - 3 = 14