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Number Series

1.1, 9, 25, 49, ?, 121. What will come at the place of question mark ?

**Answer:**Option** 1**

Solution:

1^{2} = 1.

3^{2} = 9.

5^{2} = 25.

7^{2} = 49.

**9 ^{2} = 81.**

11

2.4, 7, 12, 19, 28, ?

**Answer:**Option** 1**

Solution:

First term,

4

Second,

4+3 = 7.

Third,

7+5 = 12.

Fourth,

12+7 = 19.

Fifth,

19+9 = 28.

Therefore,

**28+11 = 39** will be the required term.

3.6, 11, 21, 36, 56, ?

**Answer:**Option** 1**

Solution:

6 (+5)→ 11 (+10)→ 21 (+15)→ 36 (+20)→ 56 (+25) → 81.

4.8, 28, 116, 584, ?

**Answer:**Option** 1**

Solution:

(8 *3) + 4 = 28
(28 *4) + 4 = 116
(116 *5) + 4 = 584
(584 *6) + 4 = 5.3, 7, 23, 95, ?

**Answer:**Option** 1**

Solution:

1st number = 3 2nd number = 3 x 2 +1 = 7

3rd number = 7 x 3 + 2 = 23

4th number = 23 x 4 + 3 = 95

5th number = 95 x 5 + 4 = 479

6.7, 26, 63, 124, 215, 342, ?

**Answer:**Option** 1**

Solution:

The terms are given in a series

(2^{3} -1) = 7

(3^{3} -1) = 26

(4^{3} -1) = 63

(5^{3} -1) = 124

(6^{3} -1) = 215

(7^{3} -1) = 342

So, the missing term is,

**(8 ^{3} -1) = 511.**

7.165, 195, 255, 285, 345, ?

**Answer:**Option** 1**

Solution:

15*11, 15*13, 15*17, 15*19, 15*23.

So, Missing number is

15*29 = 435.

165+30=195,

195+60=255,

255+30=285,

285+60=345,

345+30=375

8.3, 2, 7, 6, 11, ?

**Answer:**Option** 1**

Solution:

2^{nd} number is less by 1 than the 1^{st} number and 3^{rd} number is more by 5 than the 2^{nd} number. The same rule follows in other numbers of the series.

9.In the following number series a wrong number is given. Find out the wrong number.

150, 450, 750, 1060,1350,1650,1950

150, 450, 750, 1060,1350,1650,1950

**Answer:**Option** 1**

Solution:

By adding 300 to each term, we get the next term. 1060 is wrong term. It should be 1050.

10.5690, 5121, 4552, 3983, 3414, 2845, ?

**Answer:**Option** 1**

Solution:

By subtracting 569, we get the next term.

Required number,

= 2845-569

= 2276.