Missing or Extra Information EnVision Math Topic 2: Lesson 2-3 Problem Solving: Missing or Extra Information 2010-11 Materials needed: -Lesson 2-3 classwork pages created by us -Lesson 2-3 homework created by us 1

Rocket Math Please open your Rocket Math folder and find your… 2

…practice sheet for today. Write your name on the name line. Look to see which level you are starting with today. Then find your… 3

Down at the bottom find the level you are on today. …Rocket sheet. Down at the bottom find the level you are on today. If it is the same level as last time, write your date under the next try. If you passed last time , then you are on a new level today. You may color in the letter that you passed on your rocket. Then you will fill in the date under first try for your new level. These are our partners for the week… 4

Rocket Math Partners Ryan and Ariana Chelsie and Allison Maryan and Brandon Saul and Jayla Meadow and Mikayla Cameron, Jadyn & Ryan V. Matthew and Nicholas Elijah and Chase When I say go, find your partner and choose a spot. Decide who will be the checker first and get your answer sheet ready. I will give you the signal when you should start practicing. Then I will give you the signal when to switch. Go! (after practice – do one minute timing) If time, work on Daily Math Review. Switch classes at 1:45. 5

What strategies can I use to solve word problems? Today we have a new big question to investigate. Can someone read our big question? This year, we’ll learn strategies to solve many different types of word problems. In our last unit, you learned that no matter what type of word problem you have to solve, there are certain steps that you can follow for every word problem. Let’s refresh our memories about those steps…

What am I trying to find out? Problem Solving Steps Read and Understand ? What am I trying to find out? ? What do I know? When you have a word problem to solve, the first thing you need to do is * read and understand the problem. There are two important questions to ask yourself: * * Then you need to *make a plan and solve the problem. Once again, there are two important questions to ask yourself: * * Finally, you need to * look back and check your work. You should ask yourself: * * So far this year, we have already learned one strategy to solve word problems… Plan and Solve ? What strategy or strategies should I try? ? What is the answer? Look Back and Check ? Did I answer the question? ? Does my answer make sense?

For breakfast, Liz can eat cereal, eggs, or pancakes For breakfast, Liz can eat cereal, eggs, or pancakes. She can drink orange juice, apple juice, or milk. How many breakfast choices does she have? Read and Understand Plan and Solve Look Back and Check Can someone read this problem for us? What do we need to find out? What is one thing we know? What else do we know? Now we need a plan. What strategy can we use to solve this problem? (* make an organized list) Here is my organized list…* What would my answer be? (* 9 breakfast choices) Let’s look back and check. Did we answer the question? Does our answer make sense? Today we’ll learn two new problem solving strategies. cereal – orange juice eggs – orange juice pancakes – orange juice cereal – apple juice eggs – apple juice pancakes – apple juice cereal – milk eggs – milk pancakes - milk Liz has 9 breakfast choices. Make an Organized List

Ignore Extra Information Mark has $45. Nora has $40. How much money will Mark have left after he buys a CD for $15? Read and Understand Plan and Solve Take a look at this first problem. Can someone read it for us? What do we need to find out? (* how much money Mark has left) What do we know about Mark? (* has $45, is buying a CD for $15) What else do they tell us? (Nora has $40) Do we need to know that information to solve this problem? (no – we only need to know about Mark) So, we’ll need to use a new strategy. In this problem, we need to do this…* We don’t need to know that Nora had $40. That is extra information. If we ignore the extra information, how would we find out how much money Mark has left? (45-15 *) What is 5-5? * How about 4-1? * What else do I need? * What is my final answer? * Did I answer the question? Does my answer make sense? Look Back and Check $45 15 Mark has $30 left. - $ 3 Ignore Extra Information

Ignore Extra Information At the zoo, Julie saw 18 penguins. She saw 8 Adelie penguins. The rest of the penguins she saw were Rockhopper penguins. She learned that Rockhopper penguins grow to be about 5 to 8 pounds. How many Rockhopper penguins did Julie see? Read and Understand Plan and Solve Look Back and Check Let’s check out another problem that uses this strategy. Can someone read it for us? What do we need to find out? (how many Rockhopper penguins Julie saw *) What do we know that is important to answering our question? (saw 18 penguins, 8 were Adelie, rest were Rockhopper *) What information is extra? (grow to 5-8 pounds) We don’t need to know how big Rockhopper penguins can get. If we ignore the extra information, how would we find out how many Rockhopper penguins Julie saw? (18-8 *) What is 18-8? * What is my final answer? * Did I answer the question? Does my answer make sense? 18 8 - Julie saw 10 Rockhopper penguins. 10 Ignore Extra Information

Problem Solving Strategies Ignore Extra Information Make an Organized List Ignore Extra Information So, one new strategy we have learned so far today is to * ignore extra information. Let’s take a look at another kind of word problem that you might come across.

Identify Missing Information Kayla ate two tacos and an apple for lunch. The tacos had 260 calories. How many calories did Kayla eat for lunch? Read and Understand Plan and Solve Can someone read this problem? What do we need to find out? (how many calories Kayla ate for lunch *) What do we know? (ate two tacos and an apple, tacos had 260 calories *) What would I need to do to find out how many total calories she ate? (add up the calories for the tacos and the apple) Uh, oh. What don’t they tell me in this problem? (how many calories the apple is) So, we’ll need to use a new strategy. In this problem, we need to do this…* We can’t solve this problem because there is * not enough information. We need to tell what is missing. What other information do we need to solve this problem? * Look Back and Check not enough information I need to know how many calories the apple had. Identify Missing Information

Identify Missing Information June only has quarters and pennies in her coin collection. She has 85 coins in all. How many quarters does June have in her collection? Read and Understand Plan and Solve Look Back and Check Can someone read this problem? What do we need to find out? (how many quarters June has *) What do we know? (has only quarters and pennies, has 85 coins in all *) What would I need to do to find out how many quarters she has? (subtract the number of pennies from the total) Once again, we can’t solve this problem because there is * not enough information. What is missing? What other information do we need to solve this problem? * not enough information I need to know how many pennies June has. Identify Missing Information

Make an Organized List Ignore Extra Information Problem Solving Strategies Make an Organized List Ignore Extra Information So, we’ve learned two new strategies today. Sometimes, we need to…* Then we can solve the problem. Other times, we need to…* We won’t be able to solve these problems. We can only tell what is missing. Identify Missing Information

Let’s Practice! Let’s do some practice with our two new strategies. (pass out classwork sheets) 15

not enough information Decide if each problem has extra information or not enough information. Tell any information that is not needed or that is missing. Solve if you have enough information. 1. There are 328 places for activity photographs in the yearbook. The yearbook club has decided to make most of the photographs black and white. How many color photographs will be in the yearbook? Could someone read the directions at the top of the sheet? Let’s check out number 1. Can someone read it? First we need to * decide if there is extra information or missing information. What do we need to find out? * What do we know? * How would we find the answer to our question? Is there extra information or missing information? * Next we need to * tell any information that is not needed or missing. What is missing? What do we need to know? * Last we are supposed to * solve the problem. Can we solve this problem? (no, so we are finished) not enough information I need to know how many black and white photographs there will be.

$38 46 $84 + extra information Jason is 2 years older than Kevin. Decide if each problem has extra information or not enough information. Tell any information that is not needed or that is missing. Solve if you have enough information. 2. Mrs. Song bought school supplies for her two children, Jason and Kevin. Jason is 2 years older than Kevin. She spent $38 for Kevin’s supplies and $46 for Jason’s supplies. How much money did Mrs. Song spend on school supplies? Let’s check out number 2. Can someone read it? First we need to decide if there is * extra information or missing information. What do we need to find out? * What do we know that will help us answer our question? * Is there extra information or missing information? * Next we need to tell any * information that is not needed or missing. What is not needed? * Now we need to * solve the problem. Can we solve this problem? Yes! What do we need to do? * Go ahead and solve it. What did you get? * What is our final answer to the question? * extra information 1 $38 46 Jason is 2 years older than Kevin. + $84 Mrs. Song spent $84.

not enough information Decide if each problem has extra information or not enough information. Tell any information that is not needed or that is missing. Solve if you have enough information. 3. A notebook costs $2.68 and a pen costs $1.79. Does Jasmine have enough money to buy a notebook and two pens? Let’s check out number 3. Can someone read it? First we need to decide if there is * extra information or missing information. What do we need to find out? * What do we know that will help us answer our question? * Is there extra information or missing information? * Next we need to tell any * information that is not needed or missing. What is missing? What do we need to know? * Now we need to * solve the problem. Can we solve this problem? (no – so we are finished) Now it is your turn to solve some problems. You are going to do the rest of the problems on your sheets. not enough information I need to know how much money Jasmine has.