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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 848 · 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 sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  2. 2.🔀 What does this PIN rule show?
    let pin = "172";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  3. 3.🔀 Which badge does this quiz app show?
    let marks = 48;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  4. 4.🔀 What does this PIN rule show?
    let pin = "781";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  5. 5.🔀 What does this PIN rule show?
    let pin = "914";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  6. 6.🔀 What number does this shop app show?
    let total = 500;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 When does the else part run? (a) never (b) when the test is true (c) when the test is false (d) always
  8. 8.🔀 What number does this shop app show?
    let total = 830;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 What does this PIN rule show?
    let pin = "70180";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  10. 10.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 What does this battery rule show?
    let battery = 92;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 86;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  13. 13.🔀 With if / else if / else, how many parts run? (a) all of them (b) two (c) only one (d) none
  14. 14.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 What number does this shop app show?
    let total = 720;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What does this PIN rule show?
    let pin = "3747";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 94;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  18. 18.🔀 Which badge does this quiz app show?
    let marks = 58;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  19. 19.🔀 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
  20. 20.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 What does >= mean? (a) smaller or equal (b) greater than or equal (c) less than (d) not equal
  22. 22.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What does if / else let an app do? (a) pick one of two actions (b) save a photo (c) draw a screen (d) repeat forever
  24. 24.🔀 What does this PIN rule show?
    let pin = "63968";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  25. 25.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  26. 26.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "187";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What does this battery rule show?
    let battery = 90;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  30. 30.🔀 What does this battery rule show?
    let battery = 67;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  31. 31.🔀 What does this battery rule show?
    let battery = 7;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  32. 32.🔀 What does this PIN rule show?
    let pin = "561";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  33. 33.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  34. 34.🔀 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
  35. 35.🔀 What does this battery rule show?
    let battery = 31;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 46;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 97;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  38. 38.🔀 What does this PIN rule show?
    let pin = "1137";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  39. 39.🔀 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) Silver (b) Gold (c) Bronze
  40. 40.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) => (d) ===

Answer key

  1. Ask a parent
  2. Use 4 digits
  3. Bronze
  4. Use 4 digits
  5. Use 4 digits
  6. 500
  7. when the test is false
  8. 780
  9. Use 4 digits
  10. 720
  11. Battery OK
  12. Gold
  13. only one
  14. 800
  15. 670
  16. PIN saved
  17. Gold
  18. Silver
  19. Welcome!
  20. 480
  21. greater than or equal
  22. 260
  23. pick one of two actions
  24. Use 4 digits
  25. 830
  26. 340
  27. 380
  28. Use 4 digits
  29. Battery OK
  30. Battery OK
  31. Low battery
  32. Use 4 digits
  33. Welcome!
  34. Ask a parent
  35. Battery OK
  36. Bronze
  37. Gold
  38. PIN saved
  39. Silver
  40. ===

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