# Lesson 11

Scales without Units

### 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

### Solution

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### Problem 2

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

### Solution

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### Problem 3

A model airplane is built at a scale of 1 to 72. If the model plane is 8 inches long, how many feet long is the actual airplane?

### Solution

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### Problem 4

Quadrilateral A has side lengths 3, 6, 6, and 9. Quadrilateral B is a scaled copy of A with a shortest side length equal to 2. Jada says, “Since the side lengths go down by 1 in this scaling, the perimeter goes down by 4 in total.” Do you agree with Jada? Explain your reasoning.

### Solution

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(From Unit 1, Lesson 3.)

### Problem 5

Polygon B is a scaled copy of Polygon A using a scale factor of 5. Polygon A’s area is what fraction of Polygon B’s area?

### Solution

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(From Unit 1, Lesson 6.)

### 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

### Solution

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(From Unit 1, Lesson 5.)