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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 717 · 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 = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 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!
  3. 3.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) !== (d) =>
  4. 4.🔀 What does >= mean? (a) smaller or equal (b) greater than or equal (c) less than (d) not equal
  5. 5.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What number does this shop app show?
    let total = 670;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 When does the else part run? (a) when the test is true (b) never (c) always (d) when the test is false
  8. 8.🔀 What number does this shop app show?
    let total = 600;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does if / else let an app do? (a) pick one of two actions (b) repeat forever (c) save a photo (d) draw a screen
  11. 11.🔀 What does this PIN rule show?
    let pin = "2380";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  12. 12.🔀 What number does this shop app show?
    let total = 450;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What does this PIN rule show?
    let pin = "84795";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  15. 15.🔀 With if / else if / else, how many parts run? (a) all of them (b) only one (c) none (d) two
  16. 16.🔀 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!
  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 this PIN rule show?
    let pin = "999";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  19. 19.🔀 What does this PIN rule show?
    let pin = "89279";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  20. 20.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 What number does this shop app show?
    let total = 470;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 87;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  24. 24.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 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
  26. 26.🔀 What does this battery rule show?
    let battery = 43;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  27. 27.🔀 What does this battery rule show?
    let battery = 68;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  28. 28.🔀 What does this PIN rule show?
    let pin = "444";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What does this PIN rule show?
    let pin = "595";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What does this PIN rule show?
    let pin = "51665";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 78;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  33. 33.🔀 What does this battery rule show?
    let battery = 36;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  34. 34.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  35. 35.🔀 What does this battery rule show?
    let battery = 32;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  36. 36.🔀 What does this battery rule show?
    let battery = 86;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  37. 37.🔀 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!
  38. 38.🔀 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
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 68;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  40. 40.🔀 What does this PIN rule show?
    let pin = "3573";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits

Answer key

  1. 390
  2. Welcome!
  3. ===
  4. greater than or equal
  5. 380
  6. 620
  7. when the test is false
  8. 550
  9. 320
  10. pick one of two actions
  11. PIN saved
  12. 450
  13. 770
  14. Use 4 digits
  15. only one
  16. Ask a parent
  17. Ask a parent
  18. Use 4 digits
  19. Use 4 digits
  20. 340
  21. 470
  22. Battery OK
  23. Gold
  24. 350
  25. Battery OK
  26. Battery OK
  27. Battery OK
  28. Use 4 digits
  29. Use 4 digits
  30. Use 4 digits
  31. 580
  32. Silver
  33. Battery OK
  34. Low battery
  35. Battery OK
  36. Battery OK
  37. Ask a parent
  38. Gold
  39. Silver
  40. PIN saved

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