Logical Reasoning

Sequence & Series

Medium

In the given question, a letter-number series is given with one term missing as shown by (?). Choose the missing term out of the given alternates.

Q1F, S2E, U6D, W21C, ...? ...

Y88B

Y66B

Y86B

Y44B

✅ Correct Option: 1

First letters advance by two: Q, S, U, W, Y. Last letters fall by one: F, E, D, C, B.

Numbers follow $a_{n} = a_{n-1} \times n + n$ : $1\times1+1=2$ , $2\times2+2=6$ , $6\times3+3=21$ , $21\times4+4=88$ .

So the term is Y88B.

2025: 16 May Shift 1

Find the next term (?) in the following alpha-numeric series:

A-01, D-04, G-09, J-16, M-25, ?

2025: 14 May Shift 2

How many such 5's are there in the following number sequence, each of which is immediately preceded by 3 or 4 but not immediately followed by 8 or 9?

3 5 9 5 4 5 5 3 5 8 4 5 6 7 3 5 7 5 5 4 5 2 3 5 1 0

2025: 13 May Shift 1

Find the missing number from the given alternatives.

6	10	14
9	15	21
12	20	?

2023: 1 June Shift 1

Find the missing term in the given series:

DF, GJ, KM, NQ, RT, ?

2023: 15 June Shift 2

Find out the wrong number in the sequence:

40960, 10240, 2560, 640, 200, 40, 10

2025: 24 May Shift 2

Choose the missing term out of the given alternatives:

C02T, D05S, F10Q, I17N, ?, R37E

Solution