← if / else: app rules lesson New set →

App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 990 · 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.🔀 Which badge does this quiz app show?
    let marks = 67;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  2. 2.🔀 What does if / else let an app do? (a) draw a screen (b) save a photo (c) pick one of two actions (d) repeat forever
  3. 3.🔀 With if / else if / else, how many parts run? (a) only one (b) two (c) none (d) all of them
  4. 4.🔀 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
  5. 5.🔀 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
  6. 6.🔀 Which badge does this quiz app show?
    let marks = 66;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  7. 7.🔀 What does this battery rule show?
    let battery = 55;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  8. 8.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  9. 9.🔀 What does this PIN rule show?
    let pin = "604";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  10. 10.🔀 What number does this shop app show?
    let total = 480;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 When does the else part run? (a) always (b) when the test is false (c) when the test is true (d) never
  12. 12.🔀 What does this PIN rule show?
    let pin = "294";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 29;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  14. 14.🔀 What does this PIN rule show?
    let pin = "75121";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  15. 15.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 Which badge does this quiz app show?
    let marks = 33;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  17. 17.🔀 What does this battery rule show?
    let battery = 94;
    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 = 40;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  19. 19.🔀 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!
  20. 20.🔀 Which badge does this quiz app show?
    let marks = 41;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  21. 21.🔀 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
  22. 22.🔀 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!
  23. 23.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What number does this shop app show?
    let total = 680;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 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
  26. 26.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What does >= mean? (a) smaller or equal (b) greater than or equal (c) not equal (d) less than
  28. 28.🔀 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
  29. 29.🔀 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
  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.🔀 Which badge does this quiz app show?
    let marks = 98;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  32. 32.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 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) Gold (c) Silver
  34. 34.🔀 What does this battery rule show?
    let battery = 66;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  35. 35.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) = (c) => (d) ===
  37. 37.🔀 What does this PIN rule show?
    let pin = "28714";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  38. 38.🔀 Which badge does this quiz app show?
    let marks = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  39. 39.🔀 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
  40. 40.🔀 Which badge does this quiz app show?
    let marks = 81;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver

Answer key

  1. Silver
  2. pick one of two actions
  3. only one
  4. Welcome!
  5. Ask a parent
  6. Silver
  7. Battery OK
  8. Ask a parent
  9. Use 4 digits
  10. 480
  11. when the test is false
  12. Use 4 digits
  13. Bronze
  14. Use 4 digits
  15. 380
  16. Bronze
  17. Battery OK
  18. Bronze
  19. Welcome!
  20. Bronze
  21. Battery OK
  22. Welcome!
  23. 840
  24. 630
  25. Gold
  26. 830
  27. greater than or equal
  28. Low battery
  29. Battery OK
  30. Ask a parent
  31. Gold
  32. 590
  33. Gold
  34. Battery OK
  35. 800
  36. ===
  37. Use 4 digits
  38. Bronze
  39. Battery OK
  40. Gold

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