App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 728 · 40 questions

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”.

1. 1.🔀 What number does this shop app show?
   let total = 420;
   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.🔀 What does this PIN rule show?
   let pin = "8455";
   if (pin.length === 4) {
     show("PIN saved");
   } else {
     show("Use 4 digits");
   } (a) PIN saved (b) Use 4 digits
4. 4.🔀 What does if / else let an app do? (a) pick one of two actions (b) draw a screen (c) save a photo (d) repeat forever
5. 5.🔀 What does this battery rule show?
   let battery = 32;
   if (battery < 20) {
     show("Low battery");
   } else {
     show("Battery OK");
   } (a) Low battery (b) Battery OK
6. 6.🔀 What does this battery rule show?
   let battery = 44;
   if (battery < 20) {
     show("Low battery");
   } else {
     show("Battery OK");
   } (a) Low battery (b) Battery OK
7. 7.🔀 What does this PIN rule show?
   let pin = "638";
   if (pin.length === 4) {
     show("PIN saved");
   } else {
     show("Use 4 digits");
   } (a) PIN saved (b) Use 4 digits
8. 8.🔀 What does this PIN rule show?
   let pin = "7149";
   if (pin.length === 4) {
     show("PIN saved");
   } else {
     show("Use 4 digits");
   } (a) Use 4 digits (b) PIN saved
9. 9.🔀 Which badge does this quiz app show?
   let marks = 37;
   if (marks >= 80) {
     show("Gold");
   } else if (marks >= 50) {
     show("Silver");
   } else {
     show("Bronze");
   } (a) Silver (b) Gold (c) Bronze
10. 10.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) two (d) none
11. 11.🔀 What does >= mean? (a) less than (b) not equal (c) smaller or equal (d) greater than or equal
12. 12.🔀 What number does this shop app show?
    let total = 290;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
13. 13.🔀 What does this PIN rule show?
    let pin = "76431";
    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 = 29;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    } (a) Gold (b) Bronze (c) Silver
15. 15.🔀 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!
16. 16.🔀 When does the else part run? (a) never (b) when the test is true (c) always (d) when the test is false
17. 17.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
18. 18.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
19. 19.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
20. 20.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    } (a) Welcome! (b) Ask a parent
21. 21.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
22. 22.🔀 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!
23. 23.🔀 What does this PIN rule show?
    let pin = "31259";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    } (a) Use 4 digits (b) PIN saved
24. 24.🔀 Which badge does this quiz app show?
    let marks = 95;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    } (a) Silver (b) Bronze (c) Gold
25. 25.🔀 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) Gold (c) Silver
26. 26.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    } (a) Low battery (b) Battery OK
27. 27.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
28. 28.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) !== (c) = (d) ===
29. 29.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    } (a) Low battery (b) Battery OK
30. 30.🔀 Which badge does this quiz app show?
    let marks = 70;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    } (a) Silver (b) Gold (c) Bronze
31. 31.🔀 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!
32. 32.🔀 What does this PIN rule show?
    let pin = "53521";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    } (a) PIN saved (b) Use 4 digits
33. 33.🔀 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) Bronze (b) Gold (c) Silver
34. 34.🔀 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!
35. 35.🔀 What does this PIN rule show?
    let pin = "99940";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    } (a) PIN saved (b) Use 4 digits
36. 36.🔀 Which badge does this quiz app show?
    let marks = 65;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    } (a) Gold (b) Bronze (c) Silver
37. 37.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
38. 38.🔀 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
39. 39.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
40. 40.🔀 What does this battery rule show?
    let battery = 15;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    } (a) Low battery (b) Battery OK

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