Study the pattern followed by the numbers in the two boxes below. Which number…
2025
Study the pattern followed by the numbers in the two boxes below. Which number will replace the question mark (?) in the second box?
- A.
5
- B.
4
- C.
6
- D.
7
Show answer & explanation
Correct answer: A
Concept: Certain number-grid puzzles arrange three numbers per row so that every row in every box obeys one fixed arithmetic relationship. Once that relationship is confirmed using the rows that are already fully known, the same relationship pins down any missing number in the same or a similar box.
Application:
First number | Second number | Third number |
|---|---|---|
6 | 1 | 5 |
2 | 1 | 1 |
4 | 2 | 2 |
Every row above satisfies the same relationship: the first number equals the sum of the other two numbers in that row.
Top row: 6 is the sum of 1 and 5.
Middle row: 2 is the sum of 1 and 1.
Bottom row: 4 is the sum of 2 and 2.
The second box is built the same way, so the two rows that are already complete should follow the identical relationship.
First number | Second number | Third number |
|---|---|---|
? | 3 | 2 |
7 | 1 | 6 |
8 | 3 | 5 |
Middle row: 7 is the sum of 1 and 6, so the relationship still holds.
Bottom row: 8 is the sum of 3 and 5, so the relationship holds again.
Since both known rows of the second box confirm the same relationship, the top row must follow it too: its missing first number equals the sum of its own other two numbers, 3 and 2, which is 5.
Cross-check: The same relationship can be rearranged as (first number) minus (second number) = (third number). Applying this to the second box's bottom row: 8 − 3 = 5, matching the third number already given there — an independent confirmation that this is the right relationship to use.
Hence, the number that replaces the question mark is 5.