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

Explanation:

Solution:

12 = 1.
32 = 9.
52 = 25.
72 = 49.
92 = 81.
112 = 121.

2.4, 7, 12, 19, 28, ?

Explanation:

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, ?

Explanation:

Solution:

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

4.8, 28, 116, 584, ?

Explanation:

Solution:
(8 *3) + 4 = 28 (28 *4) + 4 = 116 (116 *5) + 4 = 584 (584 *6) + 4 = 3508.

5.3, 7, 23, 95, ?

Explanation:

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, ?

Explanation:

Solution:

The terms are given in a series
(23 -1) = 7
(33 -1) = 26
(43 -1) = 63
(53 -1) = 124
(63 -1) = 215
(73 -1) = 342
So, the missing term is,
(83 -1) = 511.

7.165, 195, 255, 285, 345, ?

Explanation:

Solution:
Solution 1: Each number of given series is 15 multiplied by a prime number.
15*11, 15*13, 15*17, 15*19, 15*23.
So, Missing number is
15*29 = 435.

Solution 2: This pattern is +30 and then +60 also follow for the give series.
165+30=195,
195+60=255,
255+30=285,
285+60=345,
345+30=375

8.3, 2, 7, 6, 11, ?

Explanation:

Solution:

2nd number is less by 1 than the 1st number and 3rd number is more by 5 than the 2nd 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

Explanation:

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, ?