ESIC Nursing Officer 2016 (Shift -2)
Reasoning
Hard

Insert the missing number: [Matrix Grid] 2 5 2 3 4 3 1 2 4 36 197 ?

Appeared in: ESIC Nursing Officer 2016 (Shift -2)

Explanation

  • The puzzle follows a column-wise pattern where the number in the last row is derived from the numbers above it.
  • The specific operation is the sum of the cubes of the first three numbers in the column.
  • For the third column, the numbers are 2, 3, and 4.
  • The calculation is 2³ + 3³ + 4³ = 8 + 27 + 64.
  • The sum is 99, which is the missing number.

Why Other Options Were Wrong

  • Option A: This is an incorrect calculation. It does not follow the established pattern of summing the cubes of the numbers in the column.
  • Option C: This is an incorrect calculation. It might be the result of an arithmetic error, such as adding the numbers and multiplying by a constant, but it does not fit the sum of cubes pattern.
  • Option D: This is an incorrect calculation. It is close to the correct answer but does not result from the correct application of the sum of cubes rule (8 + 27 + 64 = 99).

Related Visual

Visual explanation — Related Visual
  • Visual 1: Infographic: A visual breakdown of the matrix, showing each column with arrows pointing downwards. Each arrow is labeled with the 'sum of cubes' operation (e.g., 2³+3³+1³) leading to the result at the bottom.
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Logical Reasoning - Matrix Puzzles as background academic context rather than a clinical decision trigger.
  • This type of question does not test clinical knowledge but assesses logical reasoning and problem-solving skills, which are essential for nurses.
  • Strong analytical skills help nurses in interpreting patient data, identifying patterns in symptoms, and making sound clinical judgments under pressure.
  • What if the pattern was row-wise? If the pattern was row-wise, you would test operations (addition, subtraction, multiplication, etc.) on the numbers 2, 5, and 2 to see if a logical sequence exists, and then apply it to the other rows. In this case, the pattern is clearly vertical.
How to Approach the Question
  • First, carefully observe the grid of numbers. Look for a potential pattern or relationship between the numbers.
  • Test for patterns column-wise (vertically). Check if an arithmetic operation (addition, subtraction, multiplication, division, squares, cubes) on the first few numbers in a column produces the last number.
  • In this case, for Column 1: Test 2+3+1=6 (Incorrect). Test 231=6 (Incorrect). Test 2²+3²+1²=4+9+1=14 (Incorrect). Test 2³+3³+1³=8+27+1=36 (Correct).
  • Verify this pattern with the second column: 5³+4³+2³ = 125+64+8 = 197. The pattern holds true.
  • Apply the confirmed pattern to the third column to find the missing number: 2³+3³+4³ = 8+27+64 = 99.
  • Select the option that matches your calculated result.
Concept Tested & Keywords
  • Concept Tested: Logical Reasoning - Matrix Puzzles
  • Stem keywords: Matrix Grid, missing number, reasoning
  • Lead-in keywords: Insert

Question ID

Qwqv6e-keMlUAq1BNQ0DSI

Practise the full ESIC Nursing Officer 2016 (Shift -2)

Attempt every question from this paper in a timed mock, then review the full solution for each one.