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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 319 · 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.🔀 When does the else part run? (a) when the test is false (b) never (c) always (d) when the test is true
  2. 2.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 Which badge does this quiz app show?
    let marks = 51;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  4. 4.🔀 What does if / else let an app do? (a) draw a screen (b) save a photo (c) repeat forever (d) pick one of two actions
  5. 5.🔀 What number does this shop app show?
    let total = 860;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does >= mean? (a) not equal (b) less than (c) greater than or equal (d) smaller or equal
  7. 7.🔀 What does this battery rule show?
    let battery = 44;
    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 = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  9. 9.🔀 What does this PIN rule show?
    let pin = "213";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  10. 10.🔀 Which badge does this quiz app show?
    let marks = 93;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  11. 11.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  12. 12.🔀 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!
  13. 13.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) all of them (d) only one
  15. 15.🔀 What does this PIN rule show?
    let pin = "38804";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 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) Bronze (b) Gold (c) Silver
  17. 17.🔀 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
  18. 18.🔀 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) Gold (b) Silver (c) Bronze
  19. 19.🔀 What does this PIN rule show?
    let pin = "149";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  21. 21.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 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!
  24. 24.🔀 What does this battery rule show?
    let battery = 17;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  25. 25.🔀 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!
  26. 26.🔀 What does this battery rule show?
    let battery = 72;
    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 = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  28. 28.🔀 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
  29. 29.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What number does this shop app show?
    let total = 310;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What does this PIN rule show?
    let pin = "37593";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 What does this battery rule show?
    let battery = 23;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  33. 33.🔀 What does this battery rule show?
    let battery = 92;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  34. 34.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 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
  36. 36.🔀 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
  37. 37.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What number does this shop app show?
    let total = 740;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What does this PIN rule show?
    let pin = "5117";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  40. 40.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) === (d) =

Answer key

  1. when the test is false
  2. 470
  3. Silver
  4. pick one of two actions
  5. 810
  6. greater than or equal
  7. Battery OK
  8. Welcome!
  9. Use 4 digits
  10. Gold
  11. 570
  12. Ask a parent
  13. 590
  14. only one
  15. Use 4 digits
  16. Bronze
  17. Ask a parent
  18. Silver
  19. Use 4 digits
  20. Silver
  21. 420
  22. 380
  23. Welcome!
  24. Low battery
  25. Welcome!
  26. Battery OK
  27. Bronze
  28. Bronze
  29. 320
  30. 310
  31. Use 4 digits
  32. Battery OK
  33. Battery OK
  34. 460
  35. Ask a parent
  36. Welcome!
  37. 390
  38. 690
  39. PIN saved
  40. ===

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