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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 203 · 40 questions
TalentJR

Developer's tip (Test, then choose): if (test) { A } else { B }: A runs when the test is true, B when it is false. else if: check from the top; the first true test wins and the rest are skipped. >= includes the number itself; > does not. === tests “is equal to”.

NameDateTime takenScore ___ / 40
  1. 1.🔀 What does this battery rule show?
    let battery = 20;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  2. 2.🔀 What number does this shop app show?
    let total = 900;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 What does this PIN rule show?
    let pin = "901";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  4. 4.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Welcome! (b) Ask a parent
  5. 5.🔀 What number does this shop app show?
    let total = 740;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 What does this battery rule show?
    let battery = 1;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  8. 8.🔀 What does this PIN rule show?
    let pin = "64134";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  9. 9.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  10. 10.🔀 What does this battery rule show?
    let battery = 64;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  11. 11.🔀 Which badge does this quiz app show?
    let marks = 64;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  12. 12.🔀 When does the else part run? (a) when the test is false (b) never (c) always (d) when the test is true
  13. 13.🔀 What does if / else let an app do? (a) draw a screen (b) save a photo (c) repeat forever (d) pick one of two actions
  14. 14.🔀 What does this battery rule show?
    let battery = 57;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  15. 15.🔀 What number does this shop app show?
    let total = 780;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What does this PIN rule show?
    let pin = "89696";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  18. 18.🔀 Which badge does this quiz app show?
    let marks = 29;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Bronze (c) Silver
  19. 19.🔀 What number does this shop app show?
    let total = 450;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does >= mean? (a) not equal (b) smaller or equal (c) greater than or equal (d) less than
  21. 21.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Welcome! (b) Ask a parent
  22. 22.🔀 What number does this shop app show?
    let total = 440;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 With if / else if / else, how many parts run? (a) all of them (b) only one (c) two (d) none
  26. 26.🔀 Which badge does this quiz app show?
    let marks = 80;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  27. 27.🔀 What does this PIN rule show?
    let pin = "722";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  28. 28.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  29. 29.🔀 What does this PIN rule show?
    let pin = "83299";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What does this PIN rule show?
    let pin = "998";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  32. 32.🔀 What does this battery rule show?
    let battery = 89;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  33. 33.🔀 What does this PIN rule show?
    let pin = "6585";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  34. 34.🔀 What does this battery rule show?
    let battery = 25;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 38;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  36. 36.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  37. 37.🔀 What does this battery rule show?
    let battery = 84;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  38. 38.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What does this battery rule show?
    let battery = 73;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  40. 40.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Battery OK
  2. 850
  3. Use 4 digits
  4. Ask a parent
  5. 690
  6. 390
  7. Low battery
  8. Use 4 digits
  9. Ask a parent
  10. Battery OK
  11. Silver
  12. when the test is false
  13. pick one of two actions
  14. Battery OK
  15. 730
  16. 400
  17. Use 4 digits
  18. Bronze
  19. 450
  20. greater than or equal
  21. Welcome!
  22. 440
  23. 490
  24. 370
  25. only one
  26. Gold
  27. Use 4 digits
  28. Low battery
  29. Use 4 digits
  30. 320
  31. Use 4 digits
  32. Battery OK
  33. PIN saved
  34. Battery OK
  35. Bronze
  36. Welcome!
  37. Battery OK
  38. 500
  39. Battery OK
  40. 260

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