# MA.912.FL.1.2

Extend previous knowledge of ratios and proportional relationships to solve real-world problems involving money and business.

### Examples

Example: A local grocery stores sells trail mix for \$1.75 per pound. If the grocery store spends \$0.82 on each pound of mix, how much will the store gain in gross profit if they sell 6.4 pounds in one day?

Example: If Juan makes \$25.00 per hour and works 40 hours per week, what is his annual salary?

General Information
Subject Area: Mathematics (B.E.S.T.)
Strand: Financial Literacy
Status: State Board Approved

## Benchmark Instructional Guide

### Terms from the K-12 Glossary

• Proportional relationships

### Vertical Alignment

Previous Benchmarks

Next Benchmarks

### Purpose and Instructional Strategies

In grade 7, students have worked with ratios and proportional relationships to solve real-world problems. In Math for Data and Financial Literacy, students utilize their understanding of proportional relationships and problem solving to solve real-world problems involving money and business, including currency exchange, taxes and simple interest. Students also use concepts of proportionality when working with relative frequencies in data.
• Throughout instruction, it will be important to help students connect the mathematical concepts to everyday experiences (MTR.7.1) as they validate conclusions by comparing them to a given situation.
• Instruction for this benchmark includes opportunities to compare two different proportional relationships to each other. Allow various methods for solving, encouraging discussion and analysis of efficient and effective solutions (MTR.4.1).
• Students should understand the difference between flat rate taxes and other tax rates. Flat rate taxes are proportional tax rates such as sales tax. Comparatively, a progressive tax is one that can vary such as an income-based tax rate increasing when income increases.

### Common Misconceptions or Errors

• Students may not understand the difference between an additive comparison and a multiplicative comparison. To help address this misconception, instruction includes the understanding that proportions are multiplicative comparisons.
• Students may incorrectly set up proportions with one of the ratios having incorrect numbers in the numerator and denominator.
• Students may need information to clarify flat tax rates versus other tax rates. When working with students related to business and taxes in this benchmark include discussions on flat tax rates.

• An online clothing store, B’s Boutique sells 24 pieces of clothing every 30 minutes, and an online athletic store sells 5 shirts every 12 minutes.
• Part A. Estimate how long it will take each store to sell 100 pieces of clothing.
• Part B. Once an online store sells 200 items, the parent company for the online site gives the selling company a bonus of 20% of their sales. Will either store make a 20% bonus in a 24-hour period?

• At a local farm in Ruskin, Florida, a box of tomatoes sells for \$8.50.
• Part A. How many boxes would they need to sell to reach the sales goal of \$8,000?
• Part B. If the farm currently employs 10 workers who can fill 285 boxes in 3 days, how many days will it take them to fill enough boxes for the farm to make more than \$8,000 on the sales of the boxes of tomatoes?

### Instructional Items

Instructional Item 1
• At We Play Sports store, they try to keep their inventory at a ratio of 7 to 4 for used equipment to new equipment. If the total inventory amount for the new equipment is \$50,250, what is the amount of inventory for the used equipment?

Instructional Item 2
• The Easy Connect company makes straps to keep luggage closed. They make some with a snap lock and some with locks that are either a combination lock or work with a special luggage app. Based on sales, they typically make 20% with a snap lock, 55% with a combination lock and 25% with an app lock. If they typically sell 1,250 straps a month, how many would they expect to sell that have combination locking straps?

*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive.

## Related Courses

This benchmark is part of these courses.
1200400: Foundational Skills in Mathematics 9-12 (Specifically in versions: 2014 - 2015, 2015 - 2022, 2022 and beyond (current))
1200388: Mathematics for Data and Financial Literacy Honors (Specifically in versions: 2022 and beyond (current))
1700600: GEAR Up 1 (Specifically in versions: 2020 - 2022, 2022 and beyond (current))
1700610: GEAR Up 2 (Specifically in versions: 2020 - 2022, 2022 and beyond (current))
1700620: GEAR Up 3 (Specifically in versions: 2020 - 2022, 2022 and beyond (current))
1700630: GEAR Up 4 (Specifically in versions: 2020 - 2022, 2022 and beyond (current))
1200384: Mathematics for Data and Financial Literacy (Specifically in versions: 2022 and beyond (current))
7912120: Access Mathematics for Data and Financial Literacy (Specifically in versions: 2022 - 2023, 2023 and beyond (current))
1209315: Mathematics for ACT and SAT (Specifically in versions: 2022 and beyond (current))
2102305: Economics and Personal Finance Honors (Specifically in versions: 2023 and beyond (current))

## Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.
MA.912.FL.1.AP.2: Solve simple real-world problems involving money using ratios or proportions.

## Related Resources

Vetted resources educators can use to teach the concepts and skills in this benchmark.

## Lesson Plan

Efficient Storage:

The topic of this MEA is work and power. Students will be assigned the task of hiring employees to complete a given task. In order to make a decision as to which candidates to hire, the students initially must calculate the required work. The power each potential employee is capable of, the days they are available to work, the percentage of work-shifts they have missed over the past 12 months, and the hourly pay rate each worker commands will be provided to assist in the decision process. Full- and/or part-time positions are available. Through data analysis, the students will need to evaluate which factors are most significant in the hiring process. For instance, some groups may prioritize speed of work, while others prioritize cost or availability/dependability.

Type: Lesson Plan

## STEM Lessons - Model Eliciting Activity

Efficient Storage:

The topic of this MEA is work and power. Students will be assigned the task of hiring employees to complete a given task. In order to make a decision as to which candidates to hire, the students initially must calculate the required work. The power each potential employee is capable of, the days they are available to work, the percentage of work-shifts they have missed over the past 12 months, and the hourly pay rate each worker commands will be provided to assist in the decision process. Full- and/or part-time positions are available. Through data analysis, the students will need to evaluate which factors are most significant in the hiring process. For instance, some groups may prioritize speed of work, while others prioritize cost or availability/dependability.