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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 613 · 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.🔀 Which badge does this quiz app show?
    let marks = 35;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  2. 2.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  3. 3.🔀 What does this PIN rule show?
    let pin = "5601";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does this PIN rule show?
    let pin = "69936";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  5. 5.🔀 With if / else if / else, how many parts run? (a) only one (b) none (c) two (d) all of them
  6. 6.🔀 What does this PIN rule show?
    let pin = "79682";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  7. 7.🔀 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
  8. 8.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  9. 9.🔀 What does this PIN rule show?
    let pin = "376";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  10. 10.🔀 What does this battery rule show?
    let battery = 5;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  11. 11.🔀 What does this PIN rule show?
    let pin = "6629";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  12. 12.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  13. 13.🔀 What does this battery rule show?
    let battery = 66;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 83;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  15. 15.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  16. 16.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) === (c) = (d) =>
  17. 17.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  18. 18.🔀 What number does this shop app show?
    let total = 360;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 Which badge does this quiz app show?
    let marks = 73;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  20. 20.🔀 What does this battery rule show?
    let battery = 53;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  21. 21.🔀 What does this PIN rule show?
    let pin = "44545";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  22. 22.🔀 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
  23. 23.🔀 What does this PIN rule show?
    let pin = "5034";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  24. 24.🔀 What does this PIN rule show?
    let pin = "4920";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  25. 25.🔀 What does this PIN rule show?
    let pin = "733";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 What does this PIN rule show?
    let pin = "460";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 45;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  28. 28.🔀 When does the else part run? (a) when the test is true (b) never (c) when the test is false (d) always
  29. 29.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) draw a screen (d) save a photo
  30. 30.🔀 What number does this shop app show?
    let total = 680;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 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
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 27;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  33. 33.🔀 What does this battery rule show?
    let battery = 35;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  34. 34.🔀 What does this battery rule show?
    let battery = 36;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  35. 35.🔀 What does this battery rule show?
    let battery = 71;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What number does this shop app show?
    let total = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What does this PIN rule show?
    let pin = "9127";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  39. 39.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  40. 40.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Bronze
  2. Welcome!
  3. PIN saved
  4. Use 4 digits
  5. only one
  6. Use 4 digits
  7. Ask a parent
  8. Ask a parent
  9. Use 4 digits
  10. Low battery
  11. PIN saved
  12. Welcome!
  13. Battery OK
  14. Gold
  15. Low battery
  16. ===
  17. Welcome!
  18. 360
  19. Silver
  20. Battery OK
  21. Use 4 digits
  22. Battery OK
  23. PIN saved
  24. PIN saved
  25. Use 4 digits
  26. Use 4 digits
  27. Bronze
  28. when the test is false
  29. pick one of two actions
  30. 630
  31. Battery OK
  32. Bronze
  33. Battery OK
  34. Battery OK
  35. Battery OK
  36. 770
  37. 510
  38. PIN saved
  39. Ask a parent
  40. 490

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