Real World Examples - Proportions7th Grade Math

November, 2012

A tree casts a 32.5 foot-long shadow at the same time a 24 foot flagpole casts a 15 foot-long shadow. Set up and solve a proportion to find the height of the tree.

32.5 feet

24 f

eet

15 feet

x

Mrs. Hanley’s geometry class is trying to approximate the height of the Washington Monument. They notice that the monument casts a 333 foot-long shadow at the same time a 5 foot-tall student casts a foot-long shadow. Approximate the height of the Washington Monument by setting up and solving a proportion.

h

333 ft

3 ft

5 ft

Michael is making a model of his father’s car. The car is 4.5 feet-tall and 11 feet-long. How long will the model car be if he uses a scale of 1 inch to 2 feet.

11 feet

x inches

Michael is making a model of his father’s car. The car is 4.5 feet-tall and 11 feet-long. How tall will the model car be if he uses a scale of 1 inch to 2 feet.

4.5

ft

x

Mrs. Garcia wants to make a small flower garden similar to the triangular garden already in her yard. She wants the new one smaller but still proportional. If the longest side of the small garden is 6 feet long, what will be the dimensions of the other two sides of her new garden?

24 ft

6 ft

16 ft

18 ft

a

b

In 2002, people in Laredo, Texas, erected the tallest flagpole in the United States. It can be seen from miles away.

According to the information in the drawing, what is the approximate height of the flagpole? (The drawing is not drawn to scale.)

A. 308 feet

B. 295 feet

C. 205 feet

D. 197 feet

A common food has 923 calories for every 6 servings. How many calories are in 11 servings of the same food?

If you can run 100 meters in 10 seconds, how long does it take you to run 12,800,000 meters (in days, hours, and minutes)?

Evarado paid $1.12 for a dozen eggs. Write and solve a proportion to determine the cost of the 3 eggs Evarado needs for a recipe.

• You estimate that you can do 12 math problems in 45 minutes. How long should it take you to do 20 math problems?