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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 529 · 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 if / else let an app do? (a) pick one of two actions (b) save a photo (c) draw a screen (d) repeat forever
  2. 2.🔀 What number does this shop app show?
    let total = 760;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 What does >= mean? (a) not equal (b) less than (c) smaller or equal (d) greater than or equal
  4. 4.🔀 What does this PIN rule show?
    let pin = "89023";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  5. 5.🔀 Which badge does this quiz app show?
    let marks = 50;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  6. 6.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 With if / else if / else, how many parts run? (a) two (b) none (c) only one (d) all of them
  8. 8.🔀 Which badge does this quiz app show?
    let marks = 80;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  9. 9.🔀 What does this battery rule show?
    let battery = 12;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  11. 11.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) => (d) !==
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 87;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  13. 13.🔀 What does this PIN rule show?
    let pin = "775";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  14. 14.🔀 What does this battery rule show?
    let battery = 1;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 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
  16. 16.🔀 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!
  17. 17.🔀 What does this PIN rule show?
    let pin = "374";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  18. 18.🔀 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
  19. 19.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 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
  22. 22.🔀 Which badge does this quiz app show?
    let marks = 25;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  23. 23.🔀 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) Silver (b) Gold (c) Bronze
  24. 24.🔀 What does this battery rule show?
    let battery = 98;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  25. 25.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  26. 26.🔀 What does this PIN rule show?
    let pin = "507";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  27. 27.🔀 What does this PIN rule show?
    let pin = "490";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  28. 28.🔀 Which badge does this quiz app show?
    let marks = 69;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  29. 29.🔀 What does this battery rule show?
    let battery = 3;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  31. 31.🔀 Which badge does this quiz app show?
    let marks = 91;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  32. 32.🔀 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
  33. 33.🔀 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!
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 31;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  35. 35.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  36. 36.🔀 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!
  37. 37.🔀 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!
  38. 38.🔀 When does the else part run? (a) always (b) when the test is false (c) when the test is true (d) never
  39. 39.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What number does this shop app show?
    let total = 430;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. pick one of two actions
  2. 710
  3. greater than or equal
  4. Use 4 digits
  5. Silver
  6. 200
  7. only one
  8. Gold
  9. Low battery
  10. Low battery
  11. ===
  12. Gold
  13. Use 4 digits
  14. Low battery
  15. Ask a parent
  16. Welcome!
  17. Use 4 digits
  18. Battery OK
  19. 830
  20. 330
  21. Battery OK
  22. Bronze
  23. Bronze
  24. Battery OK
  25. Battery OK
  26. Use 4 digits
  27. Use 4 digits
  28. Silver
  29. Low battery
  30. Bronze
  31. Gold
  32. Ask a parent
  33. Ask a parent
  34. Bronze
  35. Low battery
  36. Welcome!
  37. Ask a parent
  38. when the test is false
  39. 280
  40. 430

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