GRADE 7 MATHEMATICS (7.2) Number, operation, and quantitative reasoning. The student adds, subtracts, multiplies, or divides to solve problems and justify solutions. The student is expected to: (C) use models to add, subtract, multiply, and divide integers and connect the actions to algorithms.

Model each of the following expressions and give the value of the expression. Identify what you have chosen to use as a model for -1 and +1. 4 + -2 Model:

Value:

- 3 3 Model:

Value:

- 6 3 Model:

Value:

- 3 4 Model:

Value:

1. What mathematical concepts and vocabulary do I need to know to be able to work this problem?

2. Will the Grade 7 Mathematics Formula Chart be helpful on this problem? Why or why not? 3. Will a picture or diagram be helpful on this problem? If so, how?

4. What problem-solving strategy or strategies will I use to help solve this problem? 5. Extension (7.2C): Write the mathematical sentence modeled below.

=

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GRADE 7 MATHEMATICS (7.2) Number, operation, and quantitative reasoning. The student adds, subtracts, multiplies, or divides to solve problems and justify solutions. The student is expected to: (C) use models to add, subtract, multiply, and divide integers and connect the actions to algorithms.

Model each of the following expressions and give the value of the expression. Identify what you have chosen to use as a model for -1 and +1. 4 + -2

Model: Value: -3 × 3

Model: Value: -6 ÷ 3

Model: Value: -3 4

Model: Value:

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GRADE 7 MATHEMATICS (7.2) Number, operation, and quantitative reasoning. The student adds, subtracts, multiplies, or divides to solve problems and justify solutions. The student is expected to: (C) use models to add, subtract, multiply, and divide integers and connect the actions to algorithms.

The number line below models which expression?

-8

-6

-4

-2

0

A

(-6 ) + 2 + (-2 ) + 8 + (-6 )

B

(-6 ) + 8 + 4 + 10 + (-14 )

C

(-6 ) + 8 + (-4 ) + 10+ (-14 )

D

8 + (-4 ) + 10 + (-14 )

2

4

6

8

The weather section of the newspaper listed the temperatures for four cities as -13°F, -4°F, -2°F, 5°F. Which expression models the average temperature for these four cities? A

((-13°) (-4°) + (-2°) + 5°) 4

B

((-13°) + (-4°) + (-2°) + 5°) 4

C

(-13°) + (-4°) + (-2°) + 5° 4

D

(13° + 4° + 2° + 5°) 4

Which mathematical expression is modeled below? represents -1

A

(-8 ) ( -2 )

B

( 8 ) ( -2 )

C

(-8 ) ( 4 )

D

( -4 ) ( 2 )

Doris kept the following information about her checking account for the week of June 4 - June 11. On June 4 she had a balance of $225.

Date

Transaction

June 5 June 8 June 9 June 10 June 11

Deposited $50 Wrote check for $55 Withdrew $40 cash Deposited $125 Wrote check for $65

The sketch below shows a helicopter and a submarine. The helicopter is 298 feet above the surface while the submarine is 323 feet below the water surface.

Which expression models the amount of money Doris has in her account at the end of that week? A

225 + 50 + 55 + 40 + 125 + 65

B

225 + 50 + (-55 ) + 40 + 125 + 65

C

225 + 50 + (-55 ) + 40 + 125 + (-65 )

D

225 + 50 + (-55 ) + (-40 ) + 125 + (-65 )

298 feet

323 feet

Which expression models the number of feet the helicopter is above the submarine? A

298 + (-323)

323 C 298 (-323 ) D 298 (-323) B

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298

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