1. 0.7, 2.8, 11.2, 44.8, ?

a) 178.2

b) 177.2

c) 179

d) 179.2

Explanation: GP with common ratio 4. Hence, the next term would be 179.2 i.e., option (d).

2. 1, 5/4, 21/16, ______ what will be the nth term of the series?

a) \[\left\{1-\left(1/4\right)^{n}\right\}/\left(3/4\right)\]

b) \[\left\{1+\left(1/3\right)^{n}\right\}/\left(2/3\right)^{n}\]

c) \[\left\{\left(1/3\right)^{n}+1\right\}/\left(2/3\right)\]

d) none of these

Explanation: The formula for the n

^{th}term can be easily verified from the given terms of the series. Option (a) is correct.

3. 600, 550, 450, 300, ?

a) 50

b) 0

c) 100

d) 150

Explanation: The series follows the logic of –50, –100, –150 and hence the next term of the series should be 300 – 200 = 100. Correct answer is option (c)

4. 1, 2, 3, 6, 11, 20, 37, 68 ?

a) 125

b) 126

c) 124

d) 105

Explanation: Beginning with 6, each term of the series is the sum of the previous 3 terms. Hence, the next term would be 125. So, the answer is option (a).

5. 12, 24, 36, 48, ?, 72

a) 50

b) 55

c) 60

d) 70

Explanation: AP with common difference 12. Hence, the unknown term is 12. So option (c) is the answer.

6. 1, 6, 11, ______ what will be its 15^{th} term?

a) 46

b) 76

c) 66

d) 71

Explanation: AP with common difference 5. Hence, 15

^{th}term is 71. Answer is option (d)

7. –3, 4, 23, 60, 121?

a) 22

b) 212

c) 205

d) none of these

Explanation: +7, +19, +37, +61. Hence, the next term in the series would be 121 + 91 = 212, answer is (b).

8. 20, 26, 62, ?, 1574

a) 125

b) 150

c) 278

d) 200

Explanation: We are consecutively adding increasing powers of 6. Hence, option (c) is correct.

9. 45, 40, 35, _____ which term will be the first negative term of the series?

a) \[10^{th}\] term

b) \[11^{th}\] term

c) \[12^{th}\] term

d) \[13^{th}\] term

Explanation: The first negative term will be –5 (11

^{th}term). Hence, option (b) is the answer.

10. 1/1, 4/8, 9/27, 16/64, 25/125, ?

a) 36/49

b) 49/64

c) 36/216

d) none of these

Explanation: The numerator is represented by n

^{2}and the denominator is represented by n

^{3}. Hence, the next term in the series would be 36/216, option (c) is the answer.