App Dev Worksheet: If Else Rules
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.🔀 When does the else part run? (a) never (b) always (c) when the test is true (d) when the test is false
-
2.🔀 What does this PIN rule show?
let pin = "106";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
3.🔀 What does this battery rule show?
let battery = 45;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
4.🔀 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! -
5.🔀 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) Gold (b) Bronze (c) Silver - 6.🔀 What does >= mean? (a) not equal (b) less than (c) smaller or equal (d) greater than or equal
-
7.🔀 Which badge does this quiz app show?
let marks = 35;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze -
8.🔀 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 - 9.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) draw a screen (d) save a photo
-
10.🔀 What number does this shop app show?
let total = 350;
if (total > 500) {
total = total - 50;
}
show(total); -
11.🔀 What number does this shop app show?
let total = 370;
if (total > 500) {
total = total - 50;
}
show(total); -
12.🔀 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! -
13.🔀 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! -
14.🔀 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! -
15.🔀 What number does this shop app show?
let total = 280;
if (total > 500) {
total = total - 50;
}
show(total); -
16.🔀 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 -
17.🔀 What number does this shop app show?
let total = 430;
if (total > 500) {
total = total - 50;
}
show(total); -
18.🔀 What does this PIN rule show?
let pin = "4795";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits - 19.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) => (d) !==
-
20.🔀 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) Gold (b) Bronze (c) Silver -
21.🔀 What does this battery rule show?
let battery = 39;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
22.🔀 What does this PIN rule show?
let pin = "19539";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
23.🔀 What does this battery rule show?
let battery = 66;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
24.🔀 What does this sign-up rule show?
let age = 9;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
25.🔀 What does this battery rule show?
let battery = 73;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK - 26.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) all of them (d) none
-
27.🔀 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 -
28.🔀 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 -
29.🔀 Which badge does this quiz app show?
let marks = 53;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
30.🔀 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) Bronze (c) Gold -
31.🔀 What number does this shop app show?
let total = 660;
if (total > 500) {
total = total - 50;
}
show(total); -
32.🔀 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 -
33.🔀 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! -
34.🔀 What does this PIN rule show?
let pin = "95387";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
35.🔀 What does this PIN rule show?
let pin = "8755";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
36.🔀 What does this battery rule show?
let battery = 21;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
37.🔀 What does this PIN rule show?
let pin = "760";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
38.🔀 What does this battery rule show?
let battery = 98;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
39.🔀 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) Gold (b) Silver (c) Bronze -
40.🔀 What number does this shop app show?
let total = 510;
if (total > 500) {
total = total - 50;
}
show(total);
Answer key
- when the test is false
- Use 4 digits
- Battery OK
- Ask a parent
- Bronze
- greater than or equal
- Bronze
- Low battery
- pick one of two actions
- 350
- 370
- Ask a parent
- Ask a parent
- Welcome!
- 280
- Ask a parent
- 430
- PIN saved
- ===
- Bronze
- Battery OK
- Use 4 digits
- Battery OK
- Ask a parent
- Battery OK
- only one
- Welcome!
- Welcome!
- Silver
- Silver
- 610
- Battery OK
- Welcome!
- Use 4 digits
- PIN saved
- Battery OK
- Use 4 digits
- Battery OK
- Silver
- 460
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