PrepSter Number Series Pattern Questions Tips and Tricks

There are 3 different ways the ask Questions from Number Series –

Way to solve Number Series Type 1 Questions

Let us look at Example 1 and try to understand how to solve such questions –

Type 1.1 Question (Easy)

From the given choices select the odd man out

Option 1 : 18 Option 2 : 24 Option 3 : 42 Option 4 : 39 Option 5 : 48

This is Number Pattern type Questions, in this which have to find which number is different

• It is very clear that all 18, 24, 42, 39 and 48 are divisible by 3.
• But only, 18, 24, 42 and 48 are divisible by 2 and 39 is not

So, 39 is the answer.

Type 1.2(Hard)

From the given choices select the odd man out

Option 1 : 1 Option 2 : 9 Option 3 : 21 Option 4 : 15 Option 5 : 5 Option 6: 25

No one can’t solve this problem, if you didn’t know this fact, this fact will be handy in many Logical Problems.

Fact position of a, e, i, o u in alphabets is 1, 5, 9, 15 and 21.

In the series above all numbers overlap with this fact except 25. So, 25 is odd.

Analogy based Number Pattern Question

In this question you will be given 3 numbers as A:B::C:? and you have find the value of ? from options, example –

2197:13 :: 4096 : ?

Now, we will suggest to take a pen and paper and try to find this.

I think the first idea would have had been dividing 2197 with 13, yes a good step. Result is 169, now here is where smart people will win they just need to see 169 and they know 13*13 is 169

Now 13*13*13 = 2197. 

Now, 4096 = 16*16*16

Select the right option from the given alternatives

7:11::31: ?

Option 1 : 33 Option 2 : 37 Option 3 : 39 Option 4 : 42

Now, you wouldn’t be able to solve this problem if you haven’t practiced enough. Since, only by practice you will know about Prime number usage in number series.

7 and 11 are prime numbers, so is 31 the only prime numbers in the options is 37.

So answer is 37.

Select the right option from the given alternatives

24:90::56: ?

answer is 122, diff of 24 and 90 is 66 , therefore 56: 122

First we suggest going toNumber Series Tutorial page here before you solve this one.

135, 246, 357, 468, ?

Now, its very easy to note that for 135 next digit has a difference of 2 same pattern for 246. 

So, for 5th term it will start with 5 and next digit 5+2 and next (5+2) + 2 number is 579

23, 68, 113, 158, 203,?

Now, clearly most of you will be thinking to multiply 23 to nearest 68.(This is a step up add up type problem)

• 23 x 3 = 69, 69 – 1 = 68
• 23 x 5 = 115 – 2 = 113
• 23 x 7 = 161 – 3 = 158

2, 6, 30, 210,?

Option 1 : 1680 Option 2 : 1800 Option 3 : 1890 Option 4 : 2010

This is Step up type of problem

• 2 x 3 = 6
• 6 x 5 = 30
• 30 x 7 = 210
• 210 x 9 = 1890

Now if we had no options then, one more solution starting with prime numbers was also possible.

• 2 x 3 = 6
• 6 x 5 = 30
• 30 x 7 = 210
• 210 x 11 = 2310