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Question

Select the number from the given options, that has the same relation to the fifth number as the second and fourth numbers have with the first and third numbers respectively.

15 : 1365 :: 27 : 2817 :: 43 : ?

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
4493

Analyze the Number Relationship

The question asks to identify a consistent mathematical relationship between pairs of numbers and apply it to find the missing number. The given pairs are 15 : 1365 and 27 : 2817, and we need to find the number corresponding to 43.

Pair 1: 15 : 1365

First, let's determine the relationship between 15 and 1365. We can check the ratio:

$ M_1 = \frac{1365}{15} = 91 $

So, the relationship could be multiplying the first number by 91.

Pair 2: 27 : 2817

Now, let's check the ratio for the second pair:

$ M_2 = \frac{2817}{27} \approx 104.33 $

The multiplier is different from the first pair. This suggests the multiplier itself might depend on the first number, or the relationship isn't a simple multiplication ($N \times M$).

Observing the Pattern in Multipliers

Let's list the multipliers ($M$) found:

  • For $N=15$, $M_1 = 91$.
  • For $N=27$, $M_2 \approx 104.33$.

The multiplier increased significantly from 91 to approximately 104.33.

Pair 3: 43 : ?

We need to find the number related to 43. Let's assume the relationship follows the trend observed between the second and third pairs, where the multipliers were close.

Let's calculate the multiplier ($M_3$) if we assume the correct answer is 4493 (Option B):

$ M_3 = \frac{4493}{43} \approx 104.49 $

We notice that $M_2$ (for N=27) and $M_3$ (for N=43) are very close (approximately 104.4).

Applying the Pattern

The multipliers for N=27 and N=43 are close, suggesting the multiplier stabilizes around 104.4 for larger numbers in this sequence.

Let's apply this approximate multiplier to 43:

$ 43 \times 104.4 \approx 4489.2 $

Comparing this result to the options, 4493 is the closest value.

Result

The relationship observed is $N \rightarrow N \times M$, where the multiplier $M$ increases from 91 (for N=15) to approximately 104.4 (for N=27 and N=43). Therefore, 4493 is the most fitting answer.

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Similar Questions

  1. Out of the number-pairs listed below, three are alike in the way they are related to each other. Select the odd one.
  2. Observe the four number-pairs listed below. In three of them, the numbers are related to each other by a specific logic. Select the number pair that does not follow the same logic as the other three.
  3. If 2 is added to each even digit and 1 is subtracted from each odd digit in the number 9524367, then how many digits will appear more than once in the new number thus formed?
  4. This question is based on the five, three-digit numbers given below.

    (Left) 538 745 317 853 276 (Right)

    (Example- 697 – First digit = 6, second digit = 9 and third digit = 7)
    (NOTE: All operations to be done from left to right.)

    What will be the resultant if the third digit of the highest number is added to the second digit of the lowest number?
  5. Select the option that is related to the third number in the same way as the second number is related to the first number.
    2 : 32 :: 4 : ?
  6. Select the number from among the given options that can replace the question mark (?) in the following series.
    12496, 12448, 12424, ?
  7. Study the given pattern carefully and select the numbers from among the given options that can replace the question marks (?).

    25 ◆ 64 = 5 ; 8 ; 13
    144 ◆ 36 = 12 ; 6 ; 18
    121 ◆ 81 = ? ; ? ; ?
  8. Select the option that is similar to the following numbers in a certain manner. 

    361, 729, 841

  9. The rectangle represents a set of calculations that are common across all the given equations. Identify the calculations involved and solve the third equation on the same basis:

  10. Select the set in which the numbers are related in the same way as are the numbers of the following 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 etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

     (27, 12, 322) 

    (24, 13, 310)


Important Questions from Number Based

  1. In the following question, four number pairs are given. The number on left side of (-) is related to the number of the right side of (-) with some Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

  2. Select the set in which the numbers are related in the same way as are the number of the following set.

    (3, 7, 58)

  3. Find the odd number/letters from the given alternatives.

  4. Find the odd number/letters from the given alternatives.

  5. Identify the number which is different from the other.

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