Activity
Here are verbal descriptions of two situations, followed by tables and expressions that could help answer one of the questions in the situations.
- Situation 1: A person has 80 followers on social media. The number of followers triples each year. How many followers will she have after 4 years?
- Situation 2: A tank contains 80 gallons of water and is getting filled at a rate of 3 gallons per minute. How many gallons of water will be in the tank after 4 minutes?
Use the descriptions of Situation 1 and Situation 2 to help you answer questions 1 – 6. Be prepared to explain how the table or expression answers the question.
1. Which situation best describes ?
Situation 1
2. Which situation best describes the following table?
0 | 1 | 2 | 3 | 4 | |
80 | 240 | 720 | 2,160 | 6,480 |
Situation 1. The table shows the growth of the followers multiplied by 3 each year.
3. Which situation best describes ?
Situation 2
4. Which situation best describes ?
Situation 2. is another way of expressing .
5. Which situation best describes the following table?
0 | 1 | 2 | 3 | 4 | |
80 | 83 | 86 | 89 | 92 |
Situation 2. The table shows the gallons of water in the tank increasing by 3 gallons each minute.
6. Which situation best describes ?
Situation 1. The 81 comes from .
Video: Matching Verbal Situations to Expressions and Tables
Watch the following video to learn more about matching verbal representations of a function with tables and expressions.
Self Check
Additional Resources
Multiple Representations Verbal Scenario
Here are verbal descriptions of two situations, followed by tables and expressions that could help answer one of the questions in the situations.
A food company currently has 5 convenience stores. It is considering two plans for expanding its chain of stores.
Plan A: Open 20 new stores each year.
Plan B: Double the number of stores each year.
How many stores will there be after 5 years under each plan?
Match each representation (a table or an expression) with one situation. Be prepared to explain how the table or expression answers the question.
-
years 0 1 2 3 4 5 number of stores 5 10 20 40 80 160 -
years 0 1 2 3 4 5 number of stores 5 25 45 65 85 105
To determine which options go with which scenario, you first need to analyze each scenario.
Let’s look at Plan A.
- Plan A is to open 20 new stores each year for a food company that currently has 5 convenience stores. In both scenarios, the initial value or starting point is 5 stores, which is why in each table the first value is . If they are opening 20 additional stores each year, they are adding 20 stores to the total from the previous year. So in year 1 there would be 25 total stores, in year 2 there would be 45 total stores, and so on. These values are represented in option 6, so option 6 would represent Plan A.
- The mathematical expressions contain either multiplication or addition. Plan A is ADDING 20 stores a year, so year 5 could be represented as option 1 because it would be the initial number of stores plus 20 per year for 5 years, or .
- Option 5 is also added, and represents Plan A since is the same as .
Let’s look at Plan B.
- Plan B would also start at 5, but it says to double the number of stores each year. Double means to MULTIPLY by 2, so it would be , which is option 3.
- Since can be simplified to , option 2 also represents Plan B.
- Option 4 is the other table option, and as mentioned before, each table should have an initial value of 5 stores. Since Plan B is to double the number of stores, at the end of year 1 there should be 10 stores. When you check option 4, you can see that each term is double the term before.
Therefore, Plan A is options 1, 5, and 6, and Plan B is options 2, 3, and 4.
Try It: Multiple Representations Verbal Scenario
Represent the following scenario as a table and as two different mathematical expressions:
A tank contains 80 gallons of water and is getting filled at a rate of 3 gallons per minute. How many gallons of water will be in the tank after 4 minutes?
Compare your answer:
Here is how to represent the scenario:
The table would record time in minutes and total water in gallons. The initial value is 80 gallons, so the first entry would be and each additional entry would be 3 more than the previous entry.
Time (in minutes) | 0 | 1 | 2 | 3 | 4 |
Total of water (in gallons) | 80 | 83 | 86 | 89 | 92 |
One mathematical expression would be 80 plus 3 repeated 4 times for the 4 minutes that passed, or . This could also be simplified to or 92 gallons.