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Question

Study the given pattern carefully and select the number that can replace the question mark (?) in it.

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
81

To find the number that replaces the question mark, let's examine the pattern in the given image.

The numbers in the pattern are arranged in a triangular shape:

  • Top row: 16
  • Next row: 9, 25
  • Next row: 4, ?, 36
  • Bottom row: 1, 64, 49

Let's analyze the sequence:

  1. The numbers in each row are perfect squares: \(16 = 4^2\)\(9 = 3^2\)\(25 = 5^2\).
  2. The pattern continues with perfect squares in the subsequent rows:
    • 4, as \(4^2\)
    • 36, as \(6^2\)
    • 1, as \(1^2\)
    • 64, as \(8^2\)
    • 49, as \(7^2\)

The missing number should be a perfect square that fits the sequence between 4 (\(2^2\)) and 36 (\(6^2\)). The logical choice would be \(81 = 9^2\).

Therefore, the number that can replace the question mark is 81.

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Similar Questions

  1. Study the given pattern carefully and select the number from among the given options that can replace the question mark (?).

  2. Study the given pattern carefully and select the numbers from among the given options that would be most appropriate for replacing the question mark (?)

  3. Study the given pattern carefully and select the number from among the given options that can replace the question mark (?).
    $2$$9$$5$
    $3$$8$?
    $4$$7$$6$
    $24$$504$$30$
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Important Questions from Missing Number

  1. Study the given pattern carefully and select the number from among the given options that can replace the question mark (?) in it.

    131652
    152490
    2336?
  2. Select the set in which the numbers are related in the same way as are the numbers of the given set.

    (NOTE: Operations should be performed on the whole numbers, without breaking down the number into its 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.)

    (25, 150, 3)

    (18, 180, 5)

  3. Select the option that is related to the fifth number in the same way as the second number is related to the first number and the fourth number is related to the third number.

    7 ∶ 35 ∶∶ 21 ∶ 399 ∶∶ 4 ∶ ?

  4. Study the given pattern carefully and select the number that can replace the question mark (?) in it.

    First row - 12, 7, 32

    Second row - 17, 13, 33

    Third row - 14, 8, ?

    (NOTE : Operations should be performed on the whole numbers, without breaking down the numbers into its 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)

  5. Select the number that can replace the question mark (?) in the following pattern.

    5

    6

    7

    8

    9

    115

    206

    ?

    502

    719

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