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Construct a table in the context of a problem.
A table is useful to organize information and recognize relationships.
A table is useful to organize information and recognize relationships. Let's see an example.
Janice, Tia, and Amy collect marbles. Janice has twice as marbles as Tia. Amy has three more marbles than Tia. Next week they will buy three marbles each. The number of marbles Janice will have is the same as the number of marbles Amy will have. Find the number of marbles each of the girls has.
Let's start by writing an expression for the number of marbles they have. Let x be the number of marbles Tia has.
| Verbal Phrase | Algebraic Expression | |
|---|---|---|
| Janice | Twice as Tia | 2 x |
| Tia | - | x |
| Amy | Three more than Tia | 3 + x |
| Number of Marbles They Currently Have | Number of Marbles They Will Have Next Week | |
|---|---|---|
| Janice | 2x | 2x + 3 |
| Tia | x | x + 3 |
| Amy | 3+x | 3+x + 3 |
Now we have expressions for the number of marbles the three girls will have next week.
The number of marbles Janice will have is the same as the number of marbles Amy will have. 2x+3=3+x+3 We will sove the above equation to find the value of x. Let's start by simplifying the right-hand side.
Add terms
LHS-3=RHS-3
Subtract terms
LHS-x=RHS-x
Subtract terms
We found that x=3.
In the context of the problem, x is the number of marbles Tia has. Thus, she has 3 marbles. Since Janice has twice as marbles as Tia, she has 6 marbles. Since Amy has three more than Tia, she also has 6 marbles. Tia:& 3marbles Janice:& 6marbles Amy:& 6marbles