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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 643 · 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.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) === (c) !== (d) =
  2. 2.🔀 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
  3. 3.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  4. 4.🔀 With if / else if / else, how many parts run? (a) all of them (b) only one (c) none (d) two
  5. 5.🔀 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
  6. 6.🔀 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) Gold (b) Silver (c) Bronze
  7. 7.🔀 What does this PIN rule show?
    let pin = "4251";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 What does this battery rule show?
    let battery = 57;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  9. 9.🔀 What does this PIN rule show?
    let pin = "2236";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  10. 10.🔀 Which badge does this quiz app show?
    let marks = 63;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  11. 11.🔀 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) Bronze (b) Silver (c) Gold
  12. 12.🔀 What does this battery rule show?
    let battery = 12;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  13. 13.🔀 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!
  14. 14.🔀 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!
  15. 15.🔀 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!
  16. 16.🔀 What does this PIN rule show?
    let pin = "5709";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What does this PIN rule show?
    let pin = "86307";
    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 = 760;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What does this PIN rule show?
    let pin = "86295";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  20. 20.🔀 What does this battery rule show?
    let battery = 48;
    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 = 38;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  22. 22.🔀 What does this PIN rule show?
    let pin = "472";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  23. 23.🔀 When does the else part run? (a) when the test is true (b) when the test is false (c) always (d) never
  24. 24.🔀 What number does this shop app show?
    let total = 750;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What does this battery rule show?
    let battery = 38;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  26. 26.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What does this battery rule show?
    let battery = 95;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  28. 28.🔀 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!
  29. 29.🔀 What number does this shop app show?
    let total = 720;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does >= mean? (a) smaller or equal (b) less than (c) greater than or equal (d) not equal
  31. 31.🔀 What does this battery rule show?
    let battery = 20;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  32. 32.🔀 What number does this shop app show?
    let total = 540;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What does this PIN rule show?
    let pin = "919";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  36. 36.🔀 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
  37. 37.🔀 What does this battery rule show?
    let battery = 11;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  38. 38.🔀 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
  39. 39.🔀 What does this battery rule show?
    let battery = 6;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  40. 40.🔀 What number does this shop app show?
    let total = 650;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. ===
  2. Ask a parent
  3. 720
  4. only one
  5. pick one of two actions
  6. Gold
  7. PIN saved
  8. Battery OK
  9. PIN saved
  10. Silver
  11. Bronze
  12. Low battery
  13. Ask a parent
  14. Ask a parent
  15. Welcome!
  16. PIN saved
  17. Use 4 digits
  18. 710
  19. Use 4 digits
  20. Battery OK
  21. Bronze
  22. Use 4 digits
  23. when the test is false
  24. 700
  25. Battery OK
  26. 570
  27. Battery OK
  28. Welcome!
  29. 670
  30. greater than or equal
  31. Battery OK
  32. 490
  33. 340
  34. 320
  35. Use 4 digits
  36. Battery OK
  37. Low battery
  38. Welcome!
  39. Low battery
  40. 600

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