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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 595 · 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 PIN rule show?
    let pin = "825";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  2. 2.🔀 What number does this shop app show?
    let total = 830;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 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!
  4. 4.🔀 When does the else part run? (a) never (b) when the test is true (c) when the test is false (d) always
  5. 5.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  6. 6.🔀 What does this PIN rule show?
    let pin = "8489";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  7. 7.🔀 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) Gold (b) Silver (c) Bronze
  8. 8.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  9. 9.🔀 Which badge does this quiz app show?
    let marks = 90;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  10. 10.🔀 What does this battery rule show?
    let battery = 88;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  11. 11.🔀 What does this battery rule show?
    let battery = 52;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  12. 12.🔀 What number does this shop app show?
    let total = 500;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  14. 14.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 Which badge does this quiz app show?
    let marks = 41;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  16. 16.🔀 What does this battery rule show?
    let battery = 26;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  17. 17.🔀 What does this PIN rule show?
    let pin = "419";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  18. 18.🔀 What number does this shop app show?
    let total = 430;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What does this PIN rule show?
    let pin = "3820";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 What does this battery rule show?
    let battery = 24;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  21. 21.🔀 Which badge does this quiz app show?
    let marks = 65;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  22. 22.🔀 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
  23. 23.🔀 What does this battery rule show?
    let battery = 82;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  24. 24.🔀 Which badge does this quiz app show?
    let marks = 68;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  25. 25.🔀 What does this battery rule show?
    let battery = 11;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  26. 26.🔀 What does this battery rule show?
    let battery = 22;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 What does this PIN rule show?
    let pin = "82043";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  28. 28.🔀 What does this PIN rule show?
    let pin = "435";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What does this PIN rule show?
    let pin = "6187";
    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 = 78;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  31. 31.🔀 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) Gold (b) Bronze (c) Silver
  32. 32.🔀 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
  33. 33.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) = (d) ===
  34. 34.🔀 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
  35. 35.🔀 What number does this shop app show?
    let total = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What does this PIN rule show?
    let pin = "234";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  37. 37.🔀 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
  38. 38.🔀 What number does this shop app show?
    let total = 440;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 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
  40. 40.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Use 4 digits
  2. 780
  3. Welcome!
  4. when the test is false
  5. Welcome!
  6. PIN saved
  7. Silver
  8. Silver
  9. Gold
  10. Battery OK
  11. Battery OK
  12. 500
  13. Ask a parent
  14. 790
  15. Bronze
  16. Battery OK
  17. Use 4 digits
  18. 430
  19. PIN saved
  20. Battery OK
  21. Silver
  22. Battery OK
  23. Battery OK
  24. Silver
  25. Low battery
  26. Battery OK
  27. Use 4 digits
  28. Use 4 digits
  29. PIN saved
  30. Silver
  31. Gold
  32. pick one of two actions
  33. ===
  34. Use 4 digits
  35. 510
  36. Use 4 digits
  37. Bronze
  38. 440
  39. Welcome!
  40. 380

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