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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 951 · 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 number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 23;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  3. 3.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  4. 4.🔀 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!
  5. 5.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 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
  7. 7.🔀 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
  8. 8.🔀 What does this PIN rule show?
    let pin = "4191";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 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!
  10. 10.🔀 What does >= mean? (a) less than (b) smaller or equal (c) greater than or equal (d) not equal
  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) Bronze (b) Silver (c) Gold
  12. 12.🔀 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) Bronze (b) Gold (c) Silver
  13. 13.🔀 What does this PIN rule show?
    let pin = "3755";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  14. 14.🔀 What does this PIN rule show?
    let pin = "56298";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  15. 15.🔀 What does this PIN rule show?
    let pin = "18748";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What does this PIN rule show?
    let pin = "429";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  18. 18.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What does this PIN rule show?
    let pin = "192";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 When does the else part run? (a) always (b) when the test is true (c) when the test is false (d) never
  21. 21.🔀 What does this PIN rule show?
    let pin = "343";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  22. 22.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) === (c) = (d) =>
  23. 23.🔀 What does this battery rule show?
    let battery = 46;
    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 = 43;
    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 = "33687";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  26. 26.🔀 What number does this shop app show?
    let total = 470;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What does if / else let an app do? (a) pick one of two actions (b) save a photo (c) repeat forever (d) draw a screen
  28. 28.🔀 What does this battery rule show?
    let battery = 4;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  29. 29.🔀 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
  30. 30.🔀 What does this PIN rule show?
    let pin = "2864";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  31. 31.🔀 What does this battery rule show?
    let battery = 83;
    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 = 900;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 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
  34. 34.🔀 What number does this shop app show?
    let total = 430;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What does this battery rule show?
    let battery = 37;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 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
  37. 37.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  38. 38.🔀 What does this PIN rule show?
    let pin = "3399";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  39. 39.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  40. 40.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. 350
  2. Bronze
  3. 770
  4. Ask a parent
  5. 840
  6. Welcome!
  7. Ask a parent
  8. PIN saved
  9. Welcome!
  10. greater than or equal
  11. Bronze
  12. Bronze
  13. PIN saved
  14. Use 4 digits
  15. Use 4 digits
  16. Use 4 digits
  17. Low battery
  18. 500
  19. Use 4 digits
  20. when the test is false
  21. Use 4 digits
  22. ===
  23. Battery OK
  24. Bronze
  25. Use 4 digits
  26. 470
  27. pick one of two actions
  28. Low battery
  29. Battery OK
  30. PIN saved
  31. Battery OK
  32. 850
  33. Welcome!
  34. 430
  35. Battery OK
  36. Welcome!
  37. Ask a parent
  38. PIN saved
  39. Ask a parent
  40. 640

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