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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 314 · 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) Welcome! (b) Ask a parent
  2. 2.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 What does this battery rule show?
    let battery = 41;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 70;
    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 sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  6. 6.🔀 What does if / else let an app do? (a) save a photo (b) pick one of two actions (c) draw a screen (d) repeat forever
  7. 7.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  8. 8.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 When does the else part run? (a) always (b) never (c) when the test is true (d) when the test is false
  10. 10.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 Which badge does this quiz app show?
    let marks = 99;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  12. 12.🔀 What does this PIN rule show?
    let pin = "5269";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  13. 13.🔀 What does this battery rule show?
    let battery = 74;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  14. 14.🔀 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) Silver (b) Gold (c) Bronze
  15. 15.🔀 What does this battery rule show?
    let battery = 24;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  16. 16.🔀 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
  17. 17.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) === (c) = (d) =>
  18. 18.🔀 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
  19. 19.🔀 What number does this shop app show?
    let total = 900;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this PIN rule show?
    let pin = "181";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  21. 21.🔀 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) Silver (c) Bronze
  22. 22.🔀 What number does this shop app show?
    let total = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  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) Gold (b) Silver (c) Bronze
  24. 24.🔀 Which badge does this quiz app show?
    let marks = 49;
    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 PIN rule show?
    let pin = "58936";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  26. 26.🔀 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
  27. 27.🔀 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
  28. 28.🔀 What does this PIN rule show?
    let pin = "64414";
    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 = 68;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  30. 30.🔀 What number does this shop app show?
    let total = 220;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 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!
  32. 32.🔀 What does >= mean? (a) less than (b) smaller or equal (c) greater than or equal (d) not equal
  33. 33.🔀 What does this battery rule show?
    let battery = 75;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 22;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  35. 35.🔀 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!
  36. 36.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this battery rule show?
    let battery = 47;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  38. 38.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) all of them (d) only one
  39. 39.🔀 What does this PIN rule show?
    let pin = "3475";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  40. 40.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Ask a parent
  2. 350
  3. Battery OK
  4. Silver
  5. Welcome!
  6. pick one of two actions
  7. Battery OK
  8. 380
  9. when the test is false
  10. 720
  11. Gold
  12. PIN saved
  13. Battery OK
  14. Bronze
  15. Battery OK
  16. Battery OK
  17. ===
  18. Ask a parent
  19. 850
  20. Use 4 digits
  21. Gold
  22. 510
  23. Bronze
  24. Bronze
  25. Use 4 digits
  26. Ask a parent
  27. Welcome!
  28. Use 4 digits
  29. Battery OK
  30. 220
  31. Welcome!
  32. greater than or equal
  33. Battery OK
  34. Bronze
  35. Ask a parent
  36. 790
  37. Battery OK
  38. only one
  39. PIN saved
  40. 820

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