Math Models Unit 10 Lesson 7

2. The golden ratio is approximately _____.

1.618

3. The length of a golden rectangle is 20 cm. Find the width to the nearest centimeter.

12 cm

6. The width of a golden rectangle is 24 feet. Find the perimeter of the rectangle to the nearest foot.

126 feet

11. Abraham took a photograph of his wife, Sarah. He printed two copies of the photograph. One print was 9 by 15 and the other was a similar shape but was 12 inches wide. What was the height of the other print?

20 inches

13. The area of Sarah's face in the smaller picture was 12 square inches. What was the area of her face in the larger picture?

21⅓ square inches

4. The width of a golden rectangle is 20 cm. Find the length to the nearest centimeter.

32 cm

5. The length of a golden rectangle is 24 feet. Find the area of the rectangle to the nearest square foot.

360 square feet

9. Malia wants to add a room to her house using a ratio of 9 to 4 for its dimensions. She will make the width of the room 17 feet. How long will the room be to the nearest foot?

38 feet

7. A sunflower seed head spirals in both directions, left and right. The ratio of the number of spirals going left to the number of spirals going right is very close to the golden ratio. If there are 34 spirals going right, how many spirals are going left?

55 spirals

8. In another sunflower head, there are 89 spirals going left. How many spirals are going right?

55 spirals

12. The length of Sarah's hand in one picture was 3 inches. The length of her hand in the other picture was 4 inches. If the length of her hair in the smaller picture was 7 inches, how long was her hair in the larger picture?

9⅓ inches

1. Choose the correct definition. tessellation :

a repeating pattern that completely fills a space without creating any gaps and without overlapping the pattern

10. Select all that apply. Jason wants to add a room to his house using the golden ratio for its dimensions. He knows he wants to make the ceiling 13 feet high, and he wants to make the room 8 feet wide. How long could he make the room to the nearest foot?

• 13 feet • 21 feet