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Grade 7 Computer Science — Variables in a program

Follow what a named value holds as a program changes it line by line, and say what it holds at the end.

Name: ________________________

  1. 1.A program has set score to 6. Match each line that runs next to what score holds afterwards.

    • add 4 to score
    • take 4 away from score
    • set score to 4
    • set score to score times 4
    • add score to score
    • 2
    • 24
    • 12
    • 10
    • 4

  2. 2.A program says: set m to 9; set m to m plus m. What does m hold now?

    • a) 0
    • b) 9
    • c) 81
    • d) 18

  3. 3.A program says: set total to 4; set total to 7; print total. What appears on the screen?

    • a) 4
    • b) 11
    • c) First 4 and then 7
    • d) 7

  4. 4.A program says: set x to 3; set y to x; set x to 8. What does y hold now?

  5. 5.Sort each line by whether it changes what total holds.

    Groups: Changes it · Leaves it as it was

    • compare total with 10
    • set total to 0
    • take 2 away from total
    • print total
    • add 5 to total
    • show total on the screen

  6. 6.A program says: set a to 6; set b to 4; set a to a plus b. What does a hold now?

  7. 7.A program says: set price to 20; set price to price times 2. What does price hold now?

    • a) 2
    • b) 20
    • c) 22
    • d) 40

  8. 8.A program says: set score to 5; add 3 to score. What does score hold now?

Answer key — Grade 7 Computer Science — Variables in a program

  1. 1. add 4 to score → 10; take 4 away from score → 2; set score to 4 → 4; set score to score times 4 → 24; add score to score → 12
  2. 2. d) 18
  3. 3. d) 7
  4. 4. 3
  5. 5. add 5 to total → Changes it; print total → Leaves it as it was; set total to 0 → Changes it; show total on the screen → Leaves it as it was; take 2 away from total → Changes it; compare total with 10 → Leaves it as it was
  6. 6. 10
  7. 7. d) 40
  8. 8. 8