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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 114 · 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 = "591";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  2. 2.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  3. 3.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  4. 4.🔀 When does the else part run? (a) when the test is false (b) always (c) never (d) when the test is true
  5. 5.🔀 What does this PIN rule show?
    let pin = "511";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  6. 6.🔀 What does this battery rule show?
    let battery = 61;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  7. 7.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  8. 8.🔀 What does if / else let an app do? (a) save a photo (b) repeat forever (c) pick one of two actions (d) draw a screen
  9. 9.🔀 What number does this shop app show?
    let total = 500;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 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) Gold (b) Silver (c) Bronze
  12. 12.🔀 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
  13. 13.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  14. 14.🔀 What does this battery rule show?
    let battery = 58;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 What number does this shop app show?
    let total = 410;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What does this battery rule show?
    let battery = 84;
    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 = "27978";
    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 = 360;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this sign-up rule show?
    let age = 17;
    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 = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  22. 22.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 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) Gold (b) Bronze (c) Silver
  24. 24.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 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
  26. 26.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 39;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  28. 28.🔀 What does this PIN rule show?
    let pin = "820";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 With if / else if / else, how many parts run? (a) all of them (b) only one (c) none (d) two
  31. 31.🔀 What does this battery rule show?
    let battery = 45;
    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 = 43;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  33. 33.🔀 What does this battery rule show?
    let battery = 25;
    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 = 89;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  35. 35.🔀 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
  36. 36.🔀 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
  37. 37.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) => (c) = (d) !==
  38. 38.🔀 What does >= mean? (a) less than (b) greater than or equal (c) not equal (d) smaller or equal
  39. 39.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 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) Bronze (b) Silver (c) Gold

Answer key

  1. Use 4 digits
  2. Ask a parent
  3. Low battery
  4. when the test is false
  5. Use 4 digits
  6. Battery OK
  7. Low battery
  8. pick one of two actions
  9. 500
  10. 590
  11. Bronze
  12. Welcome!
  13. Welcome!
  14. Battery OK
  15. 410
  16. Battery OK
  17. Use 4 digits
  18. 360
  19. 230
  20. Welcome!
  21. Welcome!
  22. 390
  23. Silver
  24. 200
  25. Ask a parent
  26. 260
  27. Bronze
  28. Use 4 digits
  29. 280
  30. only one
  31. Battery OK
  32. Bronze
  33. Battery OK
  34. Gold
  35. Ask a parent
  36. Battery OK
  37. ===
  38. greater than or equal
  39. 640
  40. Bronze

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