← if / else: app rules lesson New set →

App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 940 · 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 = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 What does this PIN rule show?
    let pin = "390";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  3. 3.🔀 What does this battery rule show?
    let battery = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  4. 4.🔀 When does the else part run? (a) always (b) never (c) when the test is true (d) when the test is false
  5. 5.🔀 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
  6. 6.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 What does this PIN rule show?
    let pin = "2948";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) => (c) !== (d) ===
  10. 10.🔀 What does this PIN rule show?
    let pin = "501";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  11. 11.🔀 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!
  12. 12.🔀 What does this PIN rule show?
    let pin = "861";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  13. 13.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) only one (d) two
  14. 14.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 Which badge does this quiz app show?
    let marks = 62;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  16. 16.🔀 What does this battery rule show?
    let battery = 80;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 37;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  18. 18.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What number does this shop app show?
    let total = 290;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this PIN rule show?
    let pin = "3205";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  21. 21.🔀 What number does this shop app show?
    let total = 760;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 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
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 47;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  24. 24.🔀 What does this PIN rule show?
    let pin = "82073";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 42;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  26. 26.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  27. 27.🔀 What does if / else let an app do? (a) save a photo (b) draw a screen (c) pick one of two actions (d) repeat forever
  28. 28.🔀 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
  29. 29.🔀 What does this PIN rule show?
    let pin = "589";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  31. 31.🔀 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
  32. 32.🔀 What does this battery rule show?
    let battery = 19;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  33. 33.🔀 What does this PIN rule show?
    let pin = "4100";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  34. 34.🔀 What does this PIN rule show?
    let pin = "84304";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  35. 35.🔀 What does this battery rule show?
    let battery = 47;
    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 = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  37. 37.🔀 What does this battery rule show?
    let battery = 50;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  38. 38.🔀 What does this battery rule show?
    let battery = 37;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  39. 39.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this PIN rule show?
    let pin = "2871";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved

Answer key

  1. 280
  2. Use 4 digits
  3. Battery OK
  4. when the test is false
  5. Welcome!
  6. 800
  7. PIN saved
  8. 260
  9. ===
  10. Use 4 digits
  11. Welcome!
  12. Use 4 digits
  13. only one
  14. 470
  15. Silver
  16. Battery OK
  17. Bronze
  18. 480
  19. 290
  20. PIN saved
  21. 710
  22. Low battery
  23. Bronze
  24. Use 4 digits
  25. Bronze
  26. Ask a parent
  27. pick one of two actions
  28. Bronze
  29. Use 4 digits
  30. Low battery
  31. Welcome!
  32. Low battery
  33. PIN saved
  34. Use 4 digits
  35. Battery OK
  36. Welcome!
  37. Battery OK
  38. Battery OK
  39. 270
  40. PIN saved

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