IBM series questions latest :
1.In the following questions select the number(s) from the given options for completing the given series.
Q.2 36,24,15,9,6? a) 3 b) 6 c) 0 d) 2
Q.3 98,72,14,? a) 8 b) 6 c) 4 d) 2
Q.4 69,55,26,13,? a) 3 b) 6.5 c)13 d) 4
2.96,64,128,192,128,256,288,192, ?
Ans :384
Explanation:
After 3 terms the series repears. So 4th 5th 6th term are 2* 1st 2nd and 3rd term repectively.
While the 7th 8th 9th are 3* 1st 2nd 3rd terms. So ans=128*3=384
3.31,14,18,30,15,19, ?
Ans : 29
explanation:
31 14 18
30 15 19
29 16 20
4.If the ratio of the roots of the equation x2 – 2ax + b = 0 is equal to that of the roots x2 – 2cx + d = 0, then:
a) a2b = c2 d b) a2c = b2d
b) a2d = c2b d) d2 b = c2 a
Ans : b
Explanation :
x^2-2ax+b=0 for this eqn..roots r....R1=2a/1,R2=b/1;
x^2-2cx+d=0 for this eqn ..roots r...R3=2c/1,R4=d;
As per question ,2a/b=2c/d
=>2ad=2bc (Option b)ans
5. 0,1,2,0.5,2,3,5,1,2,0,2,1,4,2,3,?
Ans : 2
explanation :
take first four digits from series: 0,1,2,0.5
0+1=1,1/2=0.5
2,3,5,1
2+3=5,5/5=1
2,0,2,1
2+0=2,2/2=1
4,2,3,?
4+2=6,6/3=2
ans:2
6.2.2,5.5,8,36,40.5,263.25,?
Ans : 269.75
Explanation :
Lets take first two digits
5.5/2.2 = 2.5
add 2.5 + 5.5 = 8
now 36/8= 4.5
4.5+36 = 40.5
263.25/40.5 = 6.5
6.5 + 263.25 = 269.75
Ans : 269.75
7. 1,1,3,2,1,5,3,4,10,4,2,?
Ans : 10
Explanation :
1+1+1=3
2+1+2=5
3+4+3=10
4+2+4=10
8.2,7,36,4,14,225,6,21,?
Ans : 576
Explanation :
hear 36 and 225 are perfect squares of 6 and 15
and hear 15-6=9
and so that 15+9= 24
so next number is 24^2=674
9.28,14,15,22.5,24.5,61.25,64.25,?
Ans : 224.875
Explanation :
Multiply each number after 1's gap with the sequence of (0.5, 1+.05 , 2+0.5 , 3+0.5 , 4+0.5........................................)
28*0.5=14
15*1.5=22.5
24.5*2.5=61.25
64.25*3.5=224.875.
10. 2,13,2,4,8,3,8,3,5,16.?
Ans : -2,8
Explanation :
3 separate sequence
2,13,2
(2*2)4,8(13-5),3(2+1) from above series
(4*2)8,3(8-5),5(3+2)
(8*2)16,-2(3-5),8(5+3)
So answer is -2,8
