Worksheet Grade 7 Math

Harlan Bend Treatment Plant: A Scale-Drawing Worksheet

A grade 7 scale-drawing worksheet built on a fictional treatment plant site plan, where students find real lengths and areas and redraw at a new scale.

Grade: Grade 7
Subject: Math
Material: Worksheet
Time: 40 min
Prep: No prep
Materials: Calculator (optional), Ruler (optional)

Standards

7.G.A.1 Common Core Math

Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale drawing at a different scale.

How this material aligns: Items 1 through 9 compute actual lengths and the basin's actual area from a scale site plan, then reproduce the basin at a second scale, the full range of skills this standard lists.

All materials for 7.G.A.1 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-07-23.

Objectives

Students will use a map scale to convert plan measurements into real lengths in feet.
Students will reproduce a scale drawing at a new scale and find a real area from the plan.

Vocabulary

Key words: scale drawing, scale factor, sedimentation basin

Teacher overview

Engineers plan a treatment plant on paper before anything is built, and every measurement on that paper stands for a much larger real distance. This worksheet gives students the site plan of a fictional plant, the Harlan Bend Water Treatment Plant, drawn at a scale of one inch to forty feet. Students read lengths off the plan, convert them to real feet, find the real floor area of a settling basin, and then redraw one basin at a larger scale. A teaching note worth stating up front: students often forget that area does not scale the same way length does, so item 4 is a good place to slow down and have them find the real length and real width first, then multiply.

Harlan Bend Treatment Plant: A Scale-Drawing Worksheet — Grade 7 Math

Name: ____________________________ Date: ______________

Student Worksheet

Harlan Bend Water Treatment Plant is a fictional plant. Its site plan is a scale drawing. The scale is one inch on the plan equals forty feet in real life. Use that scale for every question below.

A gravel path on the plan is 5 inches long. How many feet is the real path?
The sedimentation basin is drawn as a rectangle 3 inches long. How long is the real basin?
That same basin is drawn 1.5 inches wide. How wide is the real basin?
Use your answers to items 2 and 3 to find the real area of the basin floor in square feet.
The intake pipe is drawn 4.25 inches long. How long is the real pipe, in feet?
A fence runs 260 real feet along one edge of the property. How long is that fence on the plan, in inches?
The round clearwell tank is drawn with a diameter of 2 inches. What is its real diameter, in feet?
The team redraws the plan at a new scale: one inch equals twenty feet. On the new plan, how long is the 120-foot basin?
On that same new plan, how wide is the 60-foot basin?
Explain what happens to the size of the whole drawing when the scale changes from one inch equals forty feet to one inch equals twenty feet.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key

Answer: 200 ft.
5 inches × 40 feet per inch = 200 feet.
Answer: 120 ft.
3 inches × 40 feet per inch = 120 feet.
Answer: 60 ft.
1.5 inches × 40 feet per inch = 60 feet.
Answer: 7,200 sq ft.
The real basin is 120 feet by 60 feet, so 120 × 60 = 7,200 square feet.
Answer: 170 ft.
4.25 inches × 40 feet per inch = 170 feet.
Answer: 6.5 in.
260 feet ÷ 40 feet per inch = 6.5 inches on the plan.
Answer: 80 ft.
2 inches × 40 feet per inch = 80 feet.
Answer: 6 in.
At the new scale, 120 feet ÷ 20 feet per inch = 6 inches.
Answer: 3 in.
At the new scale, 60 feet ÷ 20 feet per inch = 3 inches.
Answer: The drawing gets larger.
Each real foot now takes more space on the paper, so every length doubles and the whole plan becomes twice as long and twice as wide.

Differentiation

Support

Give students a two-column conversion table with the first row filled in (1 inch, 40 feet) and the pattern shown for 2 inches and 3 inches. Let them extend the table before answering items 1 through 5 so the scale becomes a visible rate rather than a rule to recall.

Extension

Ask students to find the real area of the basin at the new scale directly from the redrawn plan (6 inches by 3 inches), then confirm it equals their item 4 answer. Have them explain why the real area stays the same even though the drawing changed size.

ELL supports

Provide a labeled sketch showing "plan" (small, on paper) and "real" (large, on the ground) with an arrow marked "× 40." Pre-teach "scale," "length," "width," and "area" with the sketch, and allow students to answer item 10 with a labeled before-and-after drawing.

Extensions

Have students pace off a real rectangle on the school grounds, such as a garden bed or a section of parking lot, measure its length and width in feet, and draw it to a scale of one inch equals ten feet. Comparing their own scale drawing with the Harlan Bend plan makes the idea of a consistent scale concrete.