← if / else: app rules lesson New set →

App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 843 · 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 this battery rule show?
    let battery = 80;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 64;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  3. 3.🔀 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!
  4. 4.🔀 What does >= mean? (a) not equal (b) smaller or equal (c) less than (d) greater than or equal
  5. 5.🔀 What number does this shop app show?
    let total = 900;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does this PIN rule show?
    let pin = "2537";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  7. 7.🔀 Which badge does this quiz app show?
    let marks = 76;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  8. 8.🔀 What does this battery rule show?
    let battery = 41;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  9. 9.🔀 What number does this shop app show?
    let total = 700;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 With if / else if / else, how many parts run? (a) none (b) all of them (c) only one (d) two
  12. 12.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 83;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  14. 14.🔀 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!
  15. 15.🔀 Which badge does this quiz app show?
    let marks = 46;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  16. 16.🔀 What does this PIN rule show?
    let pin = "145";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  17. 17.🔀 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!
  18. 18.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 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!
  20. 20.🔀 When does the else part run? (a) always (b) never (c) when the test is false (d) when the test is true
  21. 21.🔀 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
  22. 22.🔀 What does this battery rule show?
    let battery = 59;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 What does this PIN rule show?
    let pin = "80562";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  24. 24.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What number does this shop app show?
    let total = 450;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  26. 26.🔀 What does this battery rule show?
    let battery = 97;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 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
  28. 28.🔀 Which badge does this quiz app show?
    let marks = 61;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  29. 29.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) !== (c) = (d) ===
  30. 30.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 Which badge does this quiz app show?
    let marks = 84;
    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 = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  33. 33.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What does this PIN rule show?
    let pin = "493";
    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 = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this battery rule show?
    let battery = 5;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  38. 38.🔀 What does this PIN rule show?
    let pin = "443";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  39. 39.🔀 What does this PIN rule show?
    let pin = "9452";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  40. 40.🔀 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!

Answer key

  1. Battery OK
  2. Silver
  3. Ask a parent
  4. greater than or equal
  5. 850
  6. PIN saved
  7. Silver
  8. Battery OK
  9. 650
  10. 490
  11. only one
  12. Battery OK
  13. Gold
  14. Welcome!
  15. Bronze
  16. Use 4 digits
  17. Welcome!
  18. 240
  19. Welcome!
  20. when the test is false
  21. pick one of two actions
  22. Battery OK
  23. Use 4 digits
  24. 390
  25. 450
  26. Battery OK
  27. Low battery
  28. Silver
  29. ===
  30. 840
  31. Gold
  32. Ask a parent
  33. 420
  34. Use 4 digits
  35. Low battery
  36. 370
  37. Low battery
  38. Use 4 digits
  39. PIN saved
  40. Welcome!

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