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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 374 · 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 = 23;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Silver (c) Gold
  2. 2.🔀 What does if / else let an app do? (a) pick one of two actions (b) draw a screen (c) repeat forever (d) save a photo
  3. 3.🔀 When does the else part run? (a) always (b) when the test is false (c) when the test is true (d) never
  4. 4.🔀 What does this battery rule show?
    let battery = 57;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  5. 5.🔀 What does this battery rule show?
    let battery = 5;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  6. 6.🔀 What number does this shop app show?
    let total = 290;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 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
  8. 8.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 Which badge does this quiz app show?
    let marks = 34;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  11. 11.🔀 What does this PIN rule show?
    let pin = "5511";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  12. 12.🔀 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) Gold (b) Bronze (c) Silver
  13. 13.🔀 What does this PIN rule show?
    let pin = "6168";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 88;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  15. 15.🔀 What does this PIN rule show?
    let pin = "7764";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What does this battery rule show?
    let battery = 64;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  17. 17.🔀 What does this battery rule show?
    let battery = 84;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  18. 18.🔀 What does this battery rule show?
    let battery = 99;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  19. 19.🔀 Which badge does this quiz app show?
    let marks = 32;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  20. 20.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 What does this battery rule show?
    let battery = 81;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  22. 22.🔀 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!
  23. 23.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What number does this shop app show?
    let total = 220;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What does this PIN rule show?
    let pin = "6504";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  26. 26.🔀 What does this battery rule show?
    let battery = 4;
    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 = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  28. 28.🔀 What does this battery rule show?
    let battery = 34;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  29. 29.🔀 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
  30. 30.🔀 What does this sign-up rule show?
    let age = 14;
    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 = 91;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  32. 32.🔀 What does this PIN rule show?
    let pin = "49113";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  33. 33.🔀 What does this PIN rule show?
    let pin = "14099";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  34. 34.🔀 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!
  35. 35.🔀 With if / else if / else, how many parts run? (a) all of them (b) two (c) only one (d) none
  36. 36.🔀 What number does this shop app show?
    let total = 780;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 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) Gold (b) Silver (c) Bronze
  38. 38.🔀 What does this battery rule show?
    let battery = 54;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  39. 39.🔀 What does this battery rule show?
    let battery = 80;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  40. 40.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Bronze
  2. pick one of two actions
  3. when the test is false
  4. Battery OK
  5. Low battery
  6. 290
  7. Welcome!
  8. 350
  9. 570
  10. Bronze
  11. PIN saved
  12. Silver
  13. PIN saved
  14. Gold
  15. PIN saved
  16. Battery OK
  17. Battery OK
  18. Battery OK
  19. Bronze
  20. 480
  21. Battery OK
  22. Ask a parent
  23. 230
  24. 220
  25. PIN saved
  26. Low battery
  27. Battery OK
  28. Battery OK
  29. Battery OK
  30. Welcome!
  31. Gold
  32. Use 4 digits
  33. Use 4 digits
  34. Ask a parent
  35. only one
  36. 730
  37. Gold
  38. Battery OK
  39. Battery OK
  40. 270

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