WorksheetPremium

Water Quality Lab: Systems in Action

Solve systems of two linear equations through water-quality lab tasks involving samples, supplies, mixtures, and calibration.

Grade 8MathInteractive · Printable

Aligned to8.EE.C.8.c

Buy this worksheet: $1.50

Or unlock every Premium worksheet with Premium

PrintUnlock to print

Answer keyUnlock to see answers

Assign to classUnlock to assign with a class code

What’s included

Single worksheet
Auto-graded online
1 Common Core standard
Printable answer key
13 questions
Classroom-ready

Details

Format: Interactive · Printable
Grade: Grade 8
Subject: Math
Question types: Fill in the blank, Multiple choice, Short answer

About this worksheet

What students practice

Students represent water-quality lab situations with two linear equations in two variables.
Students solve systems and interpret solutions using the quantities and limits of a situation.
Students check whether a proposed solution satisfies both equations in a system.

How to use

Have students define variables and write both equations before solving. Use the final explanation to discuss why a solution must satisfy both conditions.

Curriculum

Common Core standard covered

8.EE.C.8.c

Solve real-world and math problems that lead to two linear equations in two variables.

Preview

OwlSheets.com

Name Date

Water Quality Lab: Systems in Action

Use two linear equations to solve lab planning and measurement problems.

Model the Lab Tasks

Use both conditions in each problem. For written calculations, define your variables and show your equations on separate paper.

A community science lab collects 18 full water samples. Each sample is either 100 mL or 250 mL, and their combined volume is 3,000 mL. Let x be the number of 100 mL samples and y be the number of 250 mL samples. Which system models the situation?

A. x + y = 18; 100x + 250y = 3,000
B. x + y = 3,000; 100x + 250y = 18
C. x + y = 18; 350(x + y) = 3,000
D. x + y = 18; 250x + 100y = 3,000

Technicians test 24 water samples. A basic test uses 2 strips per sample, and an expanded test uses 5 strips per sample. Each sample gets exactly one type of test. The technicians use 78 strips altogether.

How many samples receive each type of test? Basic: samples; expanded: samples.

The lab buys sample bottles and packs of test strips. Each bottle has the same price, and each strip pack has the same price. There are no extra fees.