dMAT Latin Squares: Rules, Solving Method and Practice Questions
Latin Squares is the third subtest of the dMAT Core Module. You see a 5×5 grid that is partly filled with letters, and each letter may appear only once in every row and every column. You find the letter that belongs in the field with the question mark. There are 20 tasks in 25 minutes.
How the task works
Some fields of the grid already contain letters. One empty field is marked with a question mark. Next to the grid you see the response options, and only those letters can appear anywhere in the grid.
With five rows, five columns and five letters, a completed grid has every letter exactly once in each row and exactly once in each column. That single rule is enough to work out the marked field.
Easy tasks can be solved by looking at the marked field alone. Harder ones need you to work out one or more other fields first, in your head, because you may not write in the grid.
Two checks that solve every task
- Check the field: which letters are already used? Look along the row and down the column of the marked field. Every letter you find there is ruled out. If four different letters are ruled out, the fifth is your answer.
- Check the letter: where else could it go? If step 1 leaves two or more candidates, take one candidate and ask where it could go in that row. If every other empty field in the row is blocked, because its column already has that letter, the candidate must go in the marked field. The same check works along the column.
If neither check settles it, a helper field is needed:
- Find a helper field. Look for another empty field in the same row or column as the question mark that you can solve with step 1 or step 2. Fields in rows or columns that are nearly full are the best candidates.
- Keep the helper in mind and repeat. With the helper letter placed, go back to step 1 for the marked field.
Worked example
In this grid, rows are counted from the top and columns from the left.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | C | B | |||
| 2 | A | E | D | C | |
| 3 | E | A | B | ||
| 4 | B | ? | E | A | |
| 5 | E |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
How to solve it.
- The field in row 1, column 3: row 1 already has B, C and column 3 already has A, E. Only D is left.
- The marked field: row 4 already has A, B, E and column 3 already has A, D, E. Only C is left.
Answer: C
Tips for working without notes
- Count what is missing, not what is there. In a row with three letters, name the two that are missing. Two candidates are easier to hold than three facts.
- Go to the fullest line first. A row or column with four letters gives you a helper field for nothing.
- Hold one helper at a time. Say it to yourself as a short phrase, for example "row 2, column 5 is C", before you look for the next one.
- Use your finger or the mouse pointer as a marker. You may not write, but you can keep your place on the screen.
- Do not solve fields you do not need. Only fields in the row or column of the question mark matter, plus any field you need in order to solve one of those.
Practice questions
Solve each grid in your head, then open the answer. In the explanations, rows are counted from the top and columns from the left.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | D | C | E | ||
| 2 | B | C | ? | A | |
| 3 | A | C | |||
| 4 | B | D | A | ||
| 5 | C | D | E |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: E
- The marked field: row 2 already has A, B, C and column 3 already has A, C, D. Only E is left.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | C | D | E | B | |
| 2 | ? | C | D | ||
| 3 | D | E | |||
| 4 | B | E | |||
| 5 | E | D |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: E
- E is still missing in row 2. It cannot go in columns 4, 5, because those columns already contain E. So E goes in the marked field.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | C | B | D | E | |
| 2 | |||||
| 3 | D | E | B | ||
| 4 | D | ? | A | ||
| 5 | A | D |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: E
- B is still missing in row 4. It cannot go in columns 3, 4, because those columns already contain B. So B goes in row 4, column 1.
- E is still missing in row 4. It cannot go in column 3, because that column already contains E. So E goes in the marked field.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | D | E | C | ||
| 2 | E | C | |||
| 3 | C | D | B | ||
| 4 | E | C | A | ||
| 5 | ? |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: B
- D is still missing in row 4. It cannot go in column 4, because that column already contains D. So D goes in row 4, column 1.
- A is still missing in column 4. It cannot go in row 4, because that row already contains A. So A goes in row 5, column 4.
- The marked field: row 5 already has A and column 1 already has C, D, E. Only B is left.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | ? | C | |||
| 2 | C | E | |||
| 3 | C | D | |||
| 4 | B | E | A | D | |
| 5 | A |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: E
- A is still missing in column 4. It cannot go in rows 4, 5, because those rows already contain A. So A goes in row 1, column 4.
- A is still missing in row 2. It cannot go in columns 3, 5, because those columns already contain A. So A goes in row 2, column 2.
- The field in row 3, column 2: row 3 already has C, D and column 2 already has A, E. Only B is left.
- The field in row 1, column 2: row 1 already has A, C and column 2 already has A, B, E. Only D is left.
- The marked field: row 1 already has A, C, D and column 1 already has B, C. Only E is left.
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| 1 | B | ? | |||
| 2 | E | ||||
| 3 | C | D | |||
| 4 | D | A | C | E | |
| 5 | C | A |
Which letter belongs in the field marked with a question mark?
Options: A, B, C, D, E
Show answer and explanation
Answer: D
- The field in row 1, column 4: row 1 already has B and column 4 already has A, D, E. Only C is left.
- C is still missing in row 2. It cannot go in columns 1, 3, 4, because those columns already contain C. So C goes in row 2, column 5.
- D is still missing in row 2. It cannot go in columns 1, 4, because those columns already contain D. So D goes in row 2, column 3.
- D is still missing in row 1. It cannot go in columns 1, 3, because those columns already contain D. So D goes in the marked field.
Common mistakes
- Checking only the row. The column rules out letters too. Always look both ways.
- Stopping at "two candidates". That is the moment for the second check, not for a guess.
- Trying to fill the whole grid. It is not needed and there is no time for it.
- Forgetting a helper. If you lose track, re-derive that one field. Do not restart the task.
- Running over time on a hard grid. Hard grids need several helpers. If you are past 90 seconds, choose between your remaining candidates and move on.
What to practise next
- Figure Sequences, the first Core subtest
- Mathematical Equations, the second Core subtest
- The timed dMAT sample test, which includes ten more Latin Squares
Practise Latin Squares at every level
The Yastudy practice sets include Latin Squares at three difficulty levels with solutions.
Frequently asked questions
How many Latin Squares tasks are in the dMAT?
There are 20 tasks in 25 minutes, which is 75 seconds per task.
What is the rule of a dMAT Latin Square?
The grid has 5 rows and 5 columns. Each letter can appear only once in each row and once in each column, and only the letters shown as response options can appear in the grid.
Do I have to fill in the whole grid?
No. You only need the letter for the field marked with a question mark. Sometimes you have to work out one or more other fields in your head first, but never the whole grid.
Can I write letters into the grid during the exam?
No. Note-taking is not allowed, so any field you work out on the way has to be kept in your head.
Is a dMAT Latin Square the same as Sudoku?
The row and column rule is the same idea as in Sudoku, but there are no boxes, the grid is 5×5 with letters, and you only have to find one field.
Are these practice questions from the real dMAT?
No. They are original Yastudy questions in the published format. Each has been checked by computer so that the marked field has exactly one possible letter.
Sources
Facts on this page were checked against the official sources below on 10 October 2026.
- dMAT for graduate students in India (g.a.s.t., official dMAT website)
- FAQ: dMAT for graduate students in India (g.a.s.t.)
- Digital Master Test (dMAT) for selected Master's applicants in India (APS India)
- dMAT India: List of Affected Previous Degree Fields, Version 1.0 (APS India, PDF)
- dMAT Preparatory Materials for Test Takers, General Academic Module (g.a.s.t., PDF)

