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Question

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 = ? ; ? ; ?

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
11; 9; 20

Analyzing the Number Pattern Puzzle

The question presents a pattern involving two numbers separated by a '◆' symbol, resulting in three numbers. We need to decipher this pattern to find the missing numbers for the third line.

Identifying the Pattern Rule

Let's analyze the first two lines to determine the rule:

  • Line 1: 25 ◆ 64 = 5 ; 8 ; 13
    • The first resulting number is the square root of the first input number: $\sqrt{25} = 5$.
    • The second resulting number is the square root of the second input number: $\sqrt{64} = 8$.
    • The third resulting number is the sum of the first two resulting numbers: $5 + 8 = 13$.
  • Line 2: 144 ◆ 36 = 12 ; 6 ; 18
    • Applying the same rule: $\sqrt{144} = 12$.
    • Applying the same rule: $\sqrt{36} = 6$.
    • Applying the same rule: $12 + 6 = 18$.

The pattern holds true for the first two examples. The rule is: For numbers A ◆ B, the result is $\sqrt{A}$; $\sqrt{B}$; $\sqrt{A} + \sqrt{B}$.

Applying the Pattern to Find Missing Numbers

Now, let's apply this confirmed pattern to the third line: 121 ◆ 81 = ? ; ? ; ?

  • First missing number: $\sqrt{121} = 11$.
  • Second missing number: $\sqrt{81} = 9$.
  • Third missing number: $11 + 9 = 20$.

Therefore, the numbers that replace the question marks are 11, 9, and 20.

Selecting the Correct Option

Comparing our results (11; 9; 20) with the given options:

  • Option 1: 2; 5; 7 (Incorrect)
  • Option 2: 11; 9; 20 (Correct)
  • Option 3: 12; 18; 30 (Incorrect)
  • Option 4: 7; 10; 17 (Incorrect)

The correct option is B.

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Similar Questions

  1. 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 : ?
  2. Out of the number-pairs listed below, three are alike in the way they are related to each other. Select the odd one.
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  4. 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?
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Important Questions from Number Based

  1. Four number-pairs have been given, out of which three are alike in some manner and one is different. Select the number-pair that is different. (Any operation on digits is not allowed)

  2. Four number-pairs have been given, out of which three are alike in some manner and one is different. Select the number-pair that is different.

  3. Four number-pairs have been given, out of which three are alike in some manner and one is different. Select the number-pair that is different.

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  5. Four number-pairs have been given, out of which three are alike in some manner and one is different. Select the number-pair that is different.

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