← if / else: app rules lesson New set →

App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 988 · 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 = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 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!
  3. 3.🔀 What does this battery rule show?
    let battery = 69;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 40;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  5. 5.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  6. 6.🔀 When does the else part run? (a) when the test is false (b) always (c) when the test is true (d) never
  7. 7.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 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!
  9. 9.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does >= mean? (a) smaller or equal (b) not equal (c) greater than or equal (d) less than
  11. 11.🔀 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!
  12. 12.🔀 What does this PIN rule show?
    let pin = "14335";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  13. 13.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 95;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  15. 15.🔀 What does this battery rule show?
    let battery = 59;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  16. 16.🔀 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) Silver (b) Bronze (c) Gold
  17. 17.🔀 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!
  18. 18.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) save a photo (d) draw a screen
  19. 19.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) => (d) ===
  20. 20.🔀 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
  21. 21.🔀 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) Bronze (b) Silver (c) Gold
  22. 22.🔀 What does this battery rule show?
    let battery = 24;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does this battery rule show?
    let battery = 79;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 71;
    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 PIN rule show?
    let pin = "729";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  27. 27.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  28. 28.🔀 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!
  29. 29.🔀 Which badge does this quiz app show?
    let marks = 35;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  30. 30.🔀 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
  31. 31.🔀 What does this PIN rule show?
    let pin = "7860";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 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
  33. 33.🔀 What does this battery rule show?
    let battery = 34;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  34. 34.🔀 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) Silver (c) Gold
  35. 35.🔀 What number does this shop app show?
    let total = 790;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What number does this shop app show?
    let total = 540;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this PIN rule show?
    let pin = "70428";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  38. 38.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  39. 39.🔀 What does this battery rule show?
    let battery = 7;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  40. 40.🔀 What does this battery rule show?
    let battery = 52;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK

Answer key

  1. 510
  2. Ask a parent
  3. Battery OK
  4. Bronze
  5. Ask a parent
  6. when the test is false
  7. 380
  8. Ask a parent
  9. 270
  10. greater than or equal
  11. Welcome!
  12. Use 4 digits
  13. Welcome!
  14. Gold
  15. Battery OK
  16. Gold
  17. Ask a parent
  18. pick one of two actions
  19. ===
  20. Battery OK
  21. Gold
  22. Battery OK
  23. 460
  24. Battery OK
  25. Silver
  26. Use 4 digits
  27. Low battery
  28. Ask a parent
  29. Bronze
  30. Battery OK
  31. PIN saved
  32. Battery OK
  33. Battery OK
  34. Silver
  35. 740
  36. 490
  37. Use 4 digits
  38. Welcome!
  39. Low battery
  40. Battery OK

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