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Warm Up!
Evaluate these expressions if m = 7, n = 9, and Q = 10:1. 3m + 2n =2. Q + m =3. 3Q – 4m =4. (m + 2) ÷ n =
Use a Problem Solving Plan
Chapter 1, Lesson 6
Vocabulary
• Verbal Model – describes a real world situation using words as labels and using math symbols to relate the words.
Problem Solving Plan
1. Read and Understand– Read the problem carefully. Identify the question and
any important information
2. Make a Plan– Decide on a problem solving strategy
3. Solve the Problem– Use the problem solving strategy to answer the
question
4. Look Back– Check that your answer is reasonable
Problem Solving Strategies!Strategy When to use How to use
Draw a diagram Draw a diagram when any problem involves relationships you can represent visually
Draw a diagram that shows the given information. Label any unknowns in your diagram
Look for a pattern Look for a pattern when a problem involves a series of numbers that you need to analyze
Look for a pattern in any given information. Apply and extend the pattern to help you solve the problem
Guess, Check, revise Guess, check, and revise when you need a place to start
Make a reasonable guess. Check to see if your guess solves the problem. If it does not, revise your guess and check again
Make a list or table Make a list or table when you need to record, generate, or organize information.
Generate a list, accounting for all possibilities. Look for relationships.
Work backwards Work backwards when a problem gives you an end result and you need to find beginning conditions
Work backwards from the given information until you solve the problem.
Example 1
During a kayak trip, you kayak for 2 hours, break for lunch, kayak for 3 hours, have a short break, and kayak for 2 more hours. During the first part of your trip, you travel 4 miles. You travel the same rate for the second part of the trip. During the last part of the trip, you travel twice as fast. How many miles did you travel on the kayak trip?
Step 1: Read and Understand
What do we know?? We can organize the given information on a diagram:
start end
2 hours 3 hours 2 hours
lunch break
Traveled 4 miles Traveled at the same rate
Traveled twice as fast
What do you need to find out?? You need to find the distance traveled after lunch and the distance traveled after the break in order to find the total distance traveled.
Step 2: Make a Plan
Use what you know to write a verbal model for the total distance traveled.
Distance traveled before lunch
Distance traveled after
lunch
Distance traveled after
break
How can you determine the distance traveled after lunch?How can you determine the distance traveled after the break?
Step 3: Solve the Problem
You traveled 4 miles in 2 hours before lunch. Find the rate that you traveled before lunch:
4 miles2 hours
= 2 miles per hour This means you traveled 2 miles per hour before lunch and after
lunch.
You traveled twice as fast during the last part of the trip…
2 • 2 = 4 miles per hour
Continued…
4 + 6 + 8 =You traveled a total of ____ miles.
Distance traveled before lunch
Distance traveled after
lunch
Distance traveled after
break
4 6 8
Step 4: Look back
Suppose you traveled all 7 hours at a rate of 2 miles per hour. Then you would have traveled 7 • 2 = 14 miles. Because you traveled faster during one part of the trip, you traveled more than 14 miles.
So…a distance of 18 miles seems reasonable.
Let’s practice: Writing a Verbal Model
One serving of rice weighs 2 ounces. A bag of rice weighs 90 ounces. How many full servings of rice are in the bag?
Weight of bag ÷ Weight of
1 serving
Let’s practice: Writing Verbal models
One t-shirt costs $10. How much do 15 t-shirts cost?
Number of t-shirts • cost of 1 t-shirt
Independent Practice
• Work quietly at your seat. Raise your hand if you need help
Study Guide!! (Test on Friday)
• Test will be on 1.4 – 1.6, with a few questions from 1.1 – 1.3
• This is Homework if you do not finish in class!