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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 146 · 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.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) all of them (d) only one
  2. 2.🔀 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
  3. 3.🔀 What does this PIN rule show?
    let pin = "99231";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  4. 4.🔀 What does this PIN rule show?
    let pin = "267";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  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.🔀 What does this PIN rule show?
    let pin = "2177";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  7. 7.🔀 What does this PIN rule show?
    let pin = "84416";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  8. 8.🔀 When does the else part run? (a) always (b) never (c) when the test is true (d) when the test is false
  9. 9.🔀 What does this battery rule show?
    let battery = 31;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 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!
  11. 11.🔀 What does this battery rule show?
    let battery = 51;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  12. 12.🔀 What number does this shop app show?
    let total = 700;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 What number does this shop app show?
    let total = 740;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What number does this shop app show?
    let total = 210;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 What does this PIN rule show?
    let pin = "3938";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 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
  17. 17.🔀 What does this battery rule show?
    let battery = 36;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  18. 18.🔀 Which badge does this quiz app show?
    let marks = 79;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  19. 19.🔀 Which badge does this quiz app show?
    let marks = 74;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  20. 20.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) not equal (d) less than
  21. 21.🔀 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
  22. 22.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What does this battery rule show?
    let battery = 72;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  24. 24.🔀 What does this PIN rule show?
    let pin = "1940";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  25. 25.🔀 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
  26. 26.🔀 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
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 45;
    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 = "628";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  30. 30.🔀 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!
  31. 31.🔀 What number does this shop app show?
    let total = 860;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) === (d) =
  33. 33.🔀 What does this PIN rule show?
    let pin = "836";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 36;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 82;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  36. 36.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What number does this shop app show?
    let total = 610;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What does this battery rule show?
    let battery = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 75;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  40. 40.🔀 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

Answer key

  1. only one
  2. Welcome!
  3. Use 4 digits
  4. Use 4 digits
  5. pick one of two actions
  6. PIN saved
  7. Use 4 digits
  8. when the test is false
  9. Battery OK
  10. Ask a parent
  11. Battery OK
  12. 650
  13. 690
  14. 210
  15. PIN saved
  16. Low battery
  17. Battery OK
  18. Silver
  19. Silver
  20. greater than or equal
  21. Ask a parent
  22. 320
  23. Battery OK
  24. PIN saved
  25. Low battery
  26. Welcome!
  27. Bronze
  28. Use 4 digits
  29. Welcome!
  30. Ask a parent
  31. 810
  32. ===
  33. Use 4 digits
  34. Bronze
  35. Gold
  36. 500
  37. 560
  38. Battery OK
  39. Silver
  40. Battery OK

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students