# RIDGES: a Strategy for Solving Word Problems

RIDGES: Another Strategy for Solving Word Problems

R: Read it. Go over the entire problem.

I: Identify. Look through the problem to figure out what it is you need to find out.

## D: Draw a picture.

G: Generate a word statement. Describe in words how to solve the problem.

E: Equation. Using YOUR word statement, write a mathematical equation.

S: Solve, write a sentence, and put a box around your answer.

## Use the RIDGES strategy to solve the following problems:

1. What is the speed of an airplane that flies 602 m in 2.50 s?

### R:

I: Distance = ______Time = ______Speed = ______

## E: ______

### S:

Use your favourite strategy to solve the following problems:

1. The tine on a tuning fork moves 1.0 mm in 4.0 x 103 s.

What is the speed of the tine in m/s?

1. An electron travels at a speed of 1 300 000 m/s.

How much time is required for the electron to travel 1.0 m?

1. A spaceship travelled at a speed of 3.2 x 104 km/h for 2.7 days. How far did the spaceship travel?

5.Read the following questions. Decide what each question is asking for. Read the categories of variables. Match the question to the variable that it is asking for by writing the matching letter in the box. Solve each question.

Speed / Time / Distance / Amount of Fuel
1. An airplane travels from Calgary to Toronto in 4 h 20 min. If the distance between the two cities is 4330.0 km, how fast did the plane go?
1. An earthquake created a succession of giant water waves, called tsunamis, off the coast of Japan. The waves travelled at a speed of 800.0 km/h. If the distance from the source (epicentre) of the quake to the northern coast of Australia was 8200.0 km, how long did it take the first wave to reach the Australian coast?
1. At a speed of 25.0 km/h, how far will a cyclist travel in 11.00 min?
1. A bird can fly 25 km/h. How long does it take to fly 18 km?
1. If you are driving 110.0 km/h and you look to the side to 2.5s, how far do you travel during this inattentive period?
1. A person jogs 8 complete laps around a 400.0 m track in a total time of 13.5 min. How fast did the person run (in m/s)?
1. I drove to my friend’s house yesterday in my old beat-up Ford Fairmont. My tank holds about 61 L of gas and I usually get about 8.5 km/L. It took almost 2 tanks to get from Wolfville to that town, going west. How far is it from my house to that town?

READ the following questions. Think of your own questions that ask for the same variable and solve them.

6. A person jogs eight complete laps around a 400.0 m track in a total time of 13.5 min. How fast did the person run (in m/s)?

7. Mr. Snowsky is a meteorologist and decided to gaze at the clouds one afternoon. Based on the size of an airplane, (he used to be a pilot), he estimated that the clouds were moving at a steady speed of 10 m/s. If he watched the clouds for 30 minutes, how far did they travel in that time?