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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 478 · 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 number does this shop app show?
    let total = 710;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 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
  3. 3.🔀 What does this PIN rule show?
    let pin = "7008";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 37;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  5. 5.🔀 What does this PIN rule show?
    let pin = "399";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  6. 6.🔀 What number does this shop app show?
    let total = 590;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 Which badge does this quiz app show?
    let marks = 54;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  8. 8.🔀 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) Silver (b) Gold (c) Bronze
  9. 9.🔀 What does this battery rule show?
    let battery = 10;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) => (d) ===
  11. 11.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  12. 12.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  13. 13.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  14. 14.🔀 What does this battery rule show?
    let battery = 55;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  15. 15.🔀 What does this battery rule show?
    let battery = 69;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  16. 16.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  17. 17.🔀 When does the else part run? (a) when the test is true (b) when the test is false (c) never (d) always
  18. 18.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) only one (d) all of them
  19. 19.🔀 What does this PIN rule show?
    let pin = "941";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 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!
  21. 21.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  22. 22.🔀 What does this battery rule show?
    let battery = 15;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  23. 23.🔀 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) Bronze (b) Silver (c) Gold
  24. 24.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 32;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  26. 26.🔀 What does this PIN rule show?
    let pin = "6200";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  27. 27.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 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
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 85;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  31. 31.🔀 What number does this shop app show?
    let total = 900;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 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!
  33. 33.🔀 What does this battery rule show?
    let battery = 43;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  34. 34.🔀 What number does this shop app show?
    let total = 510;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What does this PIN rule show?
    let pin = "2704";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  36. 36.🔀 What number does this shop app show?
    let total = 570;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What number does this shop app show?
    let total = 470;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What does this PIN rule show?
    let pin = "50041";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  39. 39.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) less than (d) not equal

Answer key

  1. 660
  2. pick one of two actions
  3. PIN saved
  4. Bronze
  5. Use 4 digits
  6. 540
  7. Silver
  8. Bronze
  9. Low battery
  10. ===
  11. Ask a parent
  12. Welcome!
  13. Battery OK
  14. Battery OK
  15. Battery OK
  16. Welcome!
  17. when the test is false
  18. only one
  19. Use 4 digits
  20. Welcome!
  21. Ask a parent
  22. Low battery
  23. Bronze
  24. Ask a parent
  25. Bronze
  26. PIN saved
  27. 460
  28. 330
  29. Use 4 digits
  30. Gold
  31. 850
  32. Welcome!
  33. Battery OK
  34. 460
  35. PIN saved
  36. 520
  37. 470
  38. Use 4 digits
  39. 820
  40. greater than or equal

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