← if / else: app rules lesson New set →

App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 426 · 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 = 37;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  2. 2.🔀 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!
  3. 3.🔀 What does this PIN rule show?
    let pin = "6963";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does this battery rule show?
    let battery = 96;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  5. 5.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 With if / else if / else, how many parts run? (a) all of them (b) two (c) none (d) only one
  7. 7.🔀 What does this PIN rule show?
    let pin = "8841";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 What does this PIN rule show?
    let pin = "234";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 What does this battery rule show?
    let battery = 38;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  10. 10.🔀 What does this battery rule show?
    let battery = 70;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  11. 11.🔀 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!
  12. 12.🔀 What does this battery rule show?
    let battery = 5;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  13. 13.🔀 What does this battery rule show?
    let battery = 10;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 96;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  15. 15.🔀 When does the else part run? (a) when the test is false (b) never (c) when the test is true (d) always
  16. 16.🔀 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!
  17. 17.🔀 What does this PIN rule show?
    let pin = "243";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  18. 18.🔀 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!
  19. 19.🔀 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!
  20. 20.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 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) Gold (b) Silver (c) Bronze
  22. 22.🔀 What does if / else let an app do? (a) pick one of two actions (b) repeat forever (c) draw a screen (d) save a photo
  23. 23.🔀 What does this PIN rule show?
    let pin = "81419";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  24. 24.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  25. 25.🔀 What does this PIN rule show?
    let pin = "742";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 What does this battery rule show?
    let battery = 50;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 21;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  28. 28.🔀 What does this PIN rule show?
    let pin = "3728";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What does this PIN rule show?
    let pin = "9245";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 85;
    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 = 77;
    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 PIN rule show?
    let pin = "37834";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  33. 33.🔀 What does this battery rule show?
    let battery = 71;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  34. 34.🔀 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
  35. 35.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 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
  38. 38.🔀 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
  39. 39.🔀 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
  40. 40.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Battery OK
  2. Ask a parent
  3. PIN saved
  4. Battery OK
  5. 460
  6. only one
  7. PIN saved
  8. Use 4 digits
  9. Battery OK
  10. Battery OK
  11. Ask a parent
  12. Low battery
  13. Low battery
  14. Gold
  15. when the test is false
  16. Welcome!
  17. Use 4 digits
  18. Ask a parent
  19. Welcome!
  20. 840
  21. Bronze
  22. pick one of two actions
  23. Use 4 digits
  24. Welcome!
  25. Use 4 digits
  26. Battery OK
  27. Bronze
  28. PIN saved
  29. PIN saved
  30. Gold
  31. Silver
  32. Use 4 digits
  33. Battery OK
  34. Welcome!
  35. 340
  36. 240
  37. Battery OK
  38. Low battery
  39. Gold
  40. 480

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