Number Series Test 2 (1.5 Minutes Per Question)

20*0.5 = 10
10*1 = 10 (Given as 12 in the question)
10*1.5=15
15*2 = 30
30*2.5 = 75 and so on.
12 is the wrong term in the series.

This question has a very interesting pattern ,

43 - 39 = 4 = 2*2
51- 43 =8 = 2*2*2
60 - 51 = 9 = 3*3
87 - 60 = 27 = 3*3*3
As we can see that differences between consecutive terms are of the form 2square, 2 cube, 3 square, 3 cube....
So after 87 we should have 87 + 4 square = 87 + 16 = 103 (Given as 110 in the question)
y - 87 = 16 = which implies y = 103
But the number given is 110 and hence 110 is the odd one out .

123 +17 = 140
140-34 = 106
106+ 51 = 157
157- 68=89
89 + 85 = 174.

The pattern is +20.5, +22.5, +24.5, +26.5, ....

190*0.5 - 1 = 94
94*0.5 - 1 = 46
46*0.5 - 1 =22
22*0.5 - 1 =10.

320-12 = 308
308 - 24 = 284
284-48 = 236
236 - 96 = 140
140 - 192 = -52.

3*1+1 = 3+1= 4
4*2 + 1 = 8+1 = 9
9*3 + 1 = 27+1 = 28
28*4+1 = 112+1 = 113
113*5 + 1 = 565 + 1 = 566

8 * 0.5 = 4
4 * 1.5 = 6
6 * 2.5 = 15
15 * 3.5 = 52.5

3*1 + 1 = 4

4*2 + 4 = 12

12*3 + 9 = 36 + 9 = 45

45*4 +16 = 196 (given as 198 in the question)

The pattern is *1 + 1 square, *2 + 2 square, *3 + 3 square, etc...

154 - 129 = 25 = 5*5

203 - 154 = 49 = 7*7

284 - 203 = 81 = 9*9

405 - 284 = 121 =11*11

but when we see the first two terms from left side

129 -130 = 1 = 1*1 and hence we can say that the odd term is 130 as it should be 120