What should come in place of '?' in the given series? 39 52 65 78 91 ?
104
Look at the gaps between consecutive terms to identify the pattern. In an arithmetic progression (AP) each term increases by a fixed number called the common difference (d).
- 52 − 39 = 13
- 65 − 52 = 13
- 78 − 65 = 13
- 91 − 78 = 13
The difference is constant at d = 13, confirming a simple AP. (As a check, every term is a multiple of 13: 39 = 13 × 3, 52 = 13 × 4, 65 = 13 × 5, 78 = 13 × 6, 91 = 13 × 7.)
The next term is therefore 91 + 13 = 104 (= 13 × 8), which fits the multiples-of-13 pattern perfectly. Choices such as 99, 110 or 117 break the constant step of 13, so the correct answer is 104.
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What should come in place of ‘?’ in the given series?
111, 223, 449, 903, 1813, ?
Important Questions from Sequence & Series
Which of the following options should come in place of the question mark (?) in the given series based on the English alphabetical order?
SHK, WLO, APS, ETW,?
Which of the following options should come in place of the question mark (?) in the given series based on the English alphabetical order?
EGI, KMO, QSU, WYA,?
Which of the following options should come in place of the question mark (?) in the given series?
14 15 18 23 30?
Two sets of numbers are given below. In each set of numbers, certain mathematical operation(s) on the first number result(s) in the second number. Similarly, certain mathematical operation(s) on the second number result(s) in the third number and so on. Which of the given options follows the same set of operations as in the given sets? (NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g. 13 – Operations on 13 such as adding/subtracting/multiplying to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
What should come in place of the question mark (?) in the given series based on the English alphabetical order?
TAW VCY XEA ZGC ?
