# Lesson 7

Units in Scale Drawings

Let’s explore a different way to express scales.

### Problem 1

A scale drawing of a car is presented in the following three scales. Order the scale drawings from smallest to largest. Explain your reasoning. (There are about 1.1 yards in a meter, and 2.54 cm in an inch.)

1. 1 in to 1 ft

2. 1 in to 1 m

3. 1 in to 1 yd

### Problem 2

Elena finds that the area of a house on a scale drawing is 25 square inches. The actual area of the house is 2,025 square feet. What is the scale of the drawing?

### Problem 3

Which scales are equivalent to 1 inch to 1 foot? Select all that apply.

A:

1 to 12

B:

$$\frac{1}{12}\text{ to }1$$

C:

100 to 0.12

D:

5 to 60

E:

36 to 3

F:

9 to 108

### Problem 4

Which of these scales are equivalent to 3 cm to 4 km? Select all that apply. Recall that 1 inch is 2.54 centimeters.

A:

0.75 cm to 1 km

B:

1 cm to 12 km

C:

6 mm to 2 km

D:

0.3 mm to 40 m

E:

1 inch to 7.62 km

### Problem 5

These two triangles are scaled copies of one another. The area of the smaller triangle is 9 square units. What is the area of the larger triangle? Explain or show how you know.

### Problem 6

Figures R, S, and T are all scaled copies of one another. Figure S is a scaled copy of R using a scale factor of 3. Figure T is a scaled copy of S using a scale factor of 2. Find the scale factors for each of the following:

1. From T to S
2. From S to R
3. From R to T
4. From T to R
(From Unit 2, Lesson 3.)