Help please with question 57: 4-by-4 grid with 4 symbols standing for numbers
- Thread starter M Tsan
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I would stat by replacing the symbols with letters, for ease of computation. (I am using [imath]s[/imath] for "spades", [imath]c[/imath] for "clubs", [imath]d[/imath] for "diamonds", and [imath]h[/imath] for "hearts".
You are given the sums for two of the rows and three of the columns. This gives you five equations in two unknowns. Pick any four of the equations, and solve the system for the values of the variables. Use the remaining equation to confirm that you have the correct values. Then plug those values into the fourth column to obtain the required result.
If you get stuck, please reply with a complete listing of your thoughts and efforts so far. ("Read Before Posting") Thank you!
Dr.Peterson
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What help do you need?
What I see there is five equations in four unknowns. Call the four symbols w, x, y, z, write the equations, and solve the system.
Once you show us what you've tried, we can help you either find errors, or decide what to do next.
What I see there is five equations in four unknowns. Call the four symbols w, x, y, z, write the equations, and solve the system.
Once you show us what you've tried, we can help you either find errors, or decide what to do next.
Dr.Peterson
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I see this is called a "non-verbal reasoning" test rather than a "mathematics test", so perhaps they expect you to use mere logic rather than the algebra I see written there.
This can be done by just thinking, with a lot of seeing and just a little writing. Look, for example, at the first row and the third column. The only difference in their content is changing a spade to a heart. What does that tell you about the relationship of a spade to a heart?
Look for another couple pairs that differ by one shape, and use those to find the value of that last column.
The downside of this method is that you can't tell if they were lying to you, and the sums were inconsistent (as we've seen in another problem just now). Solving completely lets you check that the problem is valid, by putting in all the values, and making sure every row and column works. Using shortcuts can be quicker if (a) they actually work, and you don't need the long systematic way after all, and (b) you completely trust the people who are testing you.
This can be done by just thinking, with a lot of seeing and just a little writing. Look, for example, at the first row and the third column. The only difference in their content is changing a spade to a heart. What does that tell you about the relationship of a spade to a heart?
Look for another couple pairs that differ by one shape, and use those to find the value of that last column.
The downside of this method is that you can't tell if they were lying to you, and the sums were inconsistent (as we've seen in another problem just now). Solving completely lets you check that the problem is valid, by putting in all the values, and making sure every row and column works. Using shortcuts can be quicker if (a) they actually work, and you don't need the long systematic way after all, and (b) you completely trust the people who are testing you.