L10 · Add and subtract positive and negative numbers

1. 1.

   Compute −5 − (2).

   Answer. −7

   −5 − (2) = −7.

2. 2.

   Compute 3 − (6).

   Answer. −3

   3 − (6) = −3.

3. 3.

   Compute −1 + (112).

   Answer. 12

   Common denominator and add: 12.

4. 4.

   Compute −4 + (114).

   Answer. −234

   Common denominator and add: −234.

5. 5.

   Compute −3 + (112). Then Ava needs 5 of that amount. What is the total they need?

   Answer. −2212

   Common denominator and add: −412. Then multiply by 5: −2212.

6. 6.

   Compute −5 − (−13). Then Malik needs 2 of that amount. What is the total they need?

   Answer. 16

   −5 − (−13) = 8. Then multiply by 2: 16.

7. 7.

   Compute −4 − (10). Then Jonah needs 3 of that amount. What is the total they need?

   Answer. −42

   −4 − (10) = −14. Then multiply by 3: −42.

8. 8.

   Compute 3 + (14). Then Malik needs 2 of that amount. What is the total they need?

   Answer. 612

   Common denominator and add: 314. Then multiply by 2: 612.

9. 9.

   Compute −2 − (11). Then Nora needs 5 of that amount. What is the total they need?

   Answer. −65

   −2 − (11) = −13. Then multiply by 5: −65.

10. 10.

    Compute −8 + (212). Then Elena needs 4 of that amount. What is the total they need?

    Answer. −42

    Common denominator and add: −1012. Then multiply by 4: −42.

11. 11.

    Think

    Luis tried this problem:
    Compute −7 + (112).
    Luis wrote −513. That is not correct. What is the right answer?

    Answer. −512

    Luis’s answer −513 is off. Common denominator and add: −512.

12. 12.

    Think

    Priya tried this problem:
    Compute 3 + (14).
    Priya wrote 315. That is not correct. What is the right answer?

    Answer. 314

    Priya’s answer 315 is off. Common denominator and add: 314.

Original extra practice. Keys are computed from the items, not guessed.