Section D Section D Checkpoint

Problem 1

Elena has 372 pennies in her piggy bank. Jada has 119 pennies in her piggy bank. Elena says that if they put their pennies together they have about 500.

Do you agree with Elena's estimate? Explain or show your reasoning.

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Solution
Sample responses:
  • Yes. Elena has almost 400 pennies and Jada has a little more than 100 so together that's about 500 pennies.
  • No. Elena is almost 30 pennies short of 400 and Jada has only about 20 pennies more than 100. Together, they have fewer than 500 pennies. 
Show Sample Response
Sample Response
Sample responses:
  • Yes. Elena has almost 400 pennies and Jada has a little more than 100 so together that's about 500 pennies.
  • No. Elena is almost 30 pennies short of 400 and Jada has only about 20 pennies more than 100. Together, they have fewer than 500 pennies. 

Problem 2

Andre has 138 trading cards. He gets 3 more sets of 8 cards. 

  1. Explain why the diagram represents the situation.
    A
  2. Write an equation that matches the diagram.
  3. How many cards does Andre have now?
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Solution
  1. Sample response: The diagram shows Andre's 138 cards and then 3 groups of 8 cards more.
  2. 138+(3×8)=?138 + (3 \times 8)= {?}
  3. 162 cards. Sample response: 3×8=243 \times 8 = 24 and 104+24=128104 + 24 = 128.
Show Sample Response
Sample Response
  1. Sample response: The diagram shows Andre's 138 cards and then 3 groups of 8 cards more.
  2. 138+(3×8)=?138 + (3 \times 8)= {?}
  3. 162 cards. Sample response: 3×8=243 \times 8 = 24 and 104+24=128104 + 24 = 128.

Problem 3

There are 4 tables in the cafeteria, with 9 students eating lunch at each table. There are also 177 students waiting in line for lunch at the cafeteria.

How many students are there in the cafeteria altogether?

  1. Write an equation for the situation. Use a "?" for the unknown.
  2. Find how many students there are in the cafeteria altogether.
Show Solution
Solution
  1. 177+(4×9)=?177 + (4 \times 9) = {?}
  2. 213 students. Sample response: 4×9=364 \times 9 = 36, 177+30=207177 + 30 = 207, 207+6=213207 + 6 = 213.
Show Sample Response
Sample Response
  1. 177+(4×9)=?177 + (4 \times 9) = {?}
  2. 213 students. Sample response: 4×9=364 \times 9 = 36, 177+30=207177 + 30 = 207, 207+6=213207 + 6 = 213.