In each of the following questions a number of possible answers are given, out of which one answer is correct. Find out the correct answer.
Insert the missing number
5. 8. 12. 17. 23. 38
(a) 29
(b) 30
(c) 32
(d) 25
Answer: (b)
Insert the missing number
4. 9. 20. 43. 90. —
(a) 185
(b) 172
(c) 179
(d) 165
Answer: (a)
Insert the missing number
1.1.4. 8. 9. 27. 16.
(a) 25
(b) 36
(c) 125
(d) 64
Answer: (d)