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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 851 · 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 = 780;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 What does this battery rule show?
    let battery = 78;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  3. 3.🔀 What does >= mean? (a) less than (b) greater than or equal (c) not equal (d) smaller or equal
  4. 4.🔀 What does this battery rule show?
    let battery = 42;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  5. 5.🔀 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
  6. 6.🔀 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
  7. 7.🔀 What number does this shop app show?
    let total = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 When does the else part run? (a) always (b) when the test is false (c) when the test is true (d) never
  9. 9.🔀 What number does this shop app show?
    let total = 650;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 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
  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 = "533";
    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 = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  14. 14.🔀 What does this PIN rule show?
    let pin = "4746";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  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) Bronze (b) Silver (c) Gold
  16. 16.🔀 What does this PIN rule show?
    let pin = "451";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What number does this shop app show?
    let total = 740;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  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 number does this shop app show?
    let total = 510;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 What does this battery rule show?
    let battery = 49;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  22. 22.🔀 What does this battery rule show?
    let battery = 69;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  23. 23.🔀 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!
  24. 24.🔀 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
  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) Silver (b) Bronze (c) Gold
  26. 26.🔀 What does this PIN rule show?
    let pin = "34749";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  27. 27.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "52344";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 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) Silver (b) Gold (c) Bronze
  32. 32.🔀 What does this battery rule show?
    let battery = 58;
    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 = "9631";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  34. 34.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 28;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 86;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  37. 37.🔀 What number does this shop app show?
    let total = 810;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) none (d) two
  39. 39.🔀 What does this PIN rule show?
    let pin = "793";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  40. 40.🔀 What does this battery rule show?
    let battery = 86;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery

Answer key

  1. 730
  2. Battery OK
  3. greater than or equal
  4. Battery OK
  5. Welcome!
  6. pick one of two actions
  7. 510
  8. when the test is false
  9. 600
  10. Welcome!
  11. Welcome!
  12. Use 4 digits
  13. Ask a parent
  14. PIN saved
  15. Bronze
  16. Use 4 digits
  17. 690
  18. Ask a parent
  19. 460
  20. 470
  21. Battery OK
  22. Battery OK
  23. Ask a parent
  24. Battery OK
  25. Bronze
  26. Use 4 digits
  27. 260
  28. Use 4 digits
  29. 480
  30. 590
  31. Gold
  32. Battery OK
  33. PIN saved
  34. 390
  35. Bronze
  36. Gold
  37. 760
  38. only one
  39. Use 4 digits
  40. Battery OK

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