assignment 3 and 4

Word Problem

Base Ten Blocks

Solve each word problems using the base-10 blocks in your  math kit or these virtual base 10 blocks .   Take pictures of your steps and paste them into the table.  Then write a description of how you found the solution.

Place Value Drawings

Solve each word problem using base-10 drawings, also known as proof drawings.  Make certain that each step you take is clearly seen in your work.  Paste in your work and then write a description of method. 

Decomposing by Place Value

Solve this problem using a decomposition strategy.  Paste your work in the table and then describe your thinking

. 

(You may choose to solve these on paper and then take a single picture of all your work and paste it to the bottom of this document.)  

Number Line

Solve this problem 2 ways by drawing number lines.  Paste in your number lines and then describe your thinking for each.

(You may choose to solve these on paper and then take a single picture of all your work and paste it to the bottom of this document.) 

Example: 

Randy has 143 brown rocks and 268 white rocks in his rock collection.  How many rocks does he have in all? 

I started by building 143 and then 268 under it. 

I noticed there were more than 10 ones so I grouped ten of the ones together to make a new 10. 

Then I noticed there were more than 10 tens so I grouped ten of the tens together to make a new 100.   That left me with 4 hundreds, 1 ten and 1 one.  Altogether that was 411. 

I started drawing 143 and 268 under it. I noticed there were more than 10 ones, so I grouped ten of the ones together to make a ten.  Then I crossed those out so I wouldn’t accidentally count them twice.   Next I noticed there were more than 10 tens so I grouped those together to make a new 100. I crossed out those 10s I regrouped. Then I counted up what was left. 4 hundreds, 1 ten and 1 one. 411. 

I started by decomposing 268 into 200, 60, and 8.  Then I added 200 to 143 which gave me 343.  Then I added 60 more which gave me 403, and finally I added 8 which was 411. 

I started by decomposing both numbers into hundreds, tens, and ones.  Then I added 100 and 200 to get 300.  Then 40 and 60 to make 100 and finally 3 and 8 to make 11.  Then I added all the partial sums together.  300 plus 100 plus 11 is 411.

I started at 268 and added 143 because 268 was the larger quantity.  I added 2 to make a friendly 270.  Then I added 100 to make 370.  When I went to add the tens I noticed that I could add 30 to make a friendly 400 and then add 10 more to make 410.  Finally I added 1 one to make 411. 

I started 143 and added 7 to make a friendly 150.  Then I added 50 to make an even friendlier 200.  Next I added the 200 which put me at 400 and then the leftover 10 which put it at 410. Last, I added the 1 that was left. The answer was 411.

Ron has 123 pennies in her penny bank.  She found 289 more pennies.  How many pennies does she have now? (2nd  Grade) 

Randy has 236 Pokemon cards and 275 Bakugan cards.  How many cards does Randy have in all? (2nd Grade) 

Word Problem

Base Ten Blocks

Solve each word problems using the base-10 blocks in your  math kit or these virtual base 10 blocks .   Take pictures of your steps and paste them into the table.  Then write a description of how you found the solution.

Place Value Drawings

Solve each word problem using base-10 drawings, also known as proof drawings.  Make certain that each step you take is clearly seen in your work.  Paste in your work and then write a description of method. 

Decomposing by Place Value

Solve this problem using a decomposition strategy.  Paste your work in the table and then describe your thinking

. 

(You may choose to solve these on paper and then take a single picture of all your work and paste it to the bottom of this document.) 

Number Line

Solve this problem 2 ways by drawing  number lines.  Paste in your number lines and then describe your thinking for each.

(You may choose to solve these on paper and then take a single picture of all your work and paste it to the bottom of this document.) 

Example: 

Randy has 242  brown rocks.  He lost 168 rocks in the sandbox.  How many rocks does Randy have left? 

I started by building 242.  I tried to subtract 8 ones but there were only 2 ones.

I decided to decompose a ten into 10 ones. That gave me 2 hundreds, 3 tens and 13 ones. I took away 8 ones, leaving 4

Next I went to subtract 6 tens but there were only 3.  I decomposed one hundred into 10 tens.  This gave me 13 tens.  I took away 6 tens leaving me with 7 tens.

Finally I took away 100, leaving 74

I drew 242. There were only 3 ones so I needed to get some more ones so I could subtract 8.  I decomposed a 10 into 10 ones.  This gave me 2 hundreds, 3 tens and 12 ones, just another way of saying 242.   I took away 8 ones which left me with 4 ones.  Then I went to take away 6 tens but there were only 3. To get some more tens I decomposed a 100 into ten 10s, giving me 13 tens.  Next I subtracted 6 tens leaving me with 7 tens.  Finally I took away 1 hundred.  This left me with 1 hundred, 7 tens and 4 ones or 174. 

When I looked at this problem, I noticed I couldn’t take 8 away from 2 without making a negative number so I knew I needed to decompose 242. I decomposed it as 200, 30, and 12. But then I saw I wouldn't be able to subtract 60 from 30 without creating a negative number so I decomposed in a different way. I split 200 into 100 and 100. I put one of the hundreds with 30, making it 130. Now I can subtract without regrouping.

I started by decomposing both numbers into hundreds tens and ones and then I started to subtract the one from the ones but I couldn’t take 8 away from 2 without making a negative number so I knew I needed to regroup the 242 in a different way.  So I grouped it as 200, 30 and 12. 12 minus 8 is 4.   Then I couldn’t easily subtract 6 tens from 4 tens without making a negative number so I needed to regroup the 230 in a different way so I split it into 100 and 130.  When I subtracted 60 from 130 I got 79 and 100 minus 100 was 0.  I added together the differences to get 74.

Teacher Notes & Noticings 

· The strategy shared above is accurate but it should be noted that it is not very efficient.  There are more efficient strategies for finding this difference.  

I started at 242. I took away 2 to make a friendly 240 and then 40 more to make a friendly 200.  Next I subtracted the rest of the tens, 20 to make 180.  Then I took away 100 to make 80 and 6 more to make 74. 

I started at 242. I took away 100 to make 142 and then 2 more to make a friendly 140..  Next I subtracted 40 to make 100 and then 20 more to make 80.  Finally I took away 6 leaving me at 74. 

Raegan had 356 beads. She used 198 beads to make a necklace.  How many beads does she have left? 

JiJi earned 300 Panda Bucks for great behavior.  He spent 182 panda bucks on a new ruler.  How many Pand Bucks does he have left?