App Dev Worksheet: Input, Processing, Output

App development lesson 7: Input, processing and output · Set 15 · 40 questions

Developer's tip (In, work, out): Input → processing → output. Input: typing, tapping, a photo, your voice. Output: a result on screen, a sound, a buzz, a pop-up. In code, the processing line works out a new value from the inputs; show() is the output.

1. 1.⚙️ What number does this app show?
   let bill = 210; // typed by the user
   let friends = 5; // typed by the user
   let share = bill / friends;
   show(share);
2. 2.Which of these is an output? (a) sorting the scores (b) a beep sound (c) adding up a bill (d) taking a photo
3. 3.⚙️ Which line does the processing (works out the answer)?
   line 1: let price = 90; // typed by the user
   line 2: let qty = 4; // typed by the user
   line 3: let total = price * qty;
   line 4: show(total); (a) line 4 (b) line 1 (c) line 2 (d) line 3
4. 4.True or false: taking a photo is an input. (a) True (b) False
5. 5.⚙️ What number does this app show?
   let bill = 284; // typed by the user
   let friends = 4; // typed by the user
   let share = bill / friends;
   show(share);
6. 6.⚙️ What number does this app show?
   let bill = 112; // typed by the user
   let friends = 2; // typed by the user
   let share = bill / friends;
   show(share);
7. 7.⚙️ What number does this app show?
   let price = 530; // typed by the user
   let off = 30; // typed by the user
   let pay = price - off;
   show(pay);
8. 8.⚙️ Which line does the processing (works out the answer)?
   line 1: let price = 15; // typed by the user
   line 2: let qty = 6; // typed by the user
   line 3: let total = price * qty;
   line 4: show(total); (a) line 3 (b) line 1 (c) line 4 (d) line 2
9. 9.True or false: speaking a command is an input. (a) False (b) True
10. 10.True or false: tapping a button is an output. (a) True (b) False
11. 11.Which of these is processing? (a) taking a photo (b) a result on screen (c) a buzz (vibration) (d) sorting the scores
12. 12.⚙️ What number does this app show?
    let price = 35; // typed by the user
    let qty = 5; // typed by the user
    let total = price * qty;
    show(total);
13. 13.⚙️ What number does this app show?
    let price = 170; // typed by the user
    let off = 20; // typed by the user
    let pay = price - off;
    show(pay);
14. 14.⚙️ What number does this app show?
    let km = 3; // typed by the user
    let metres = km * 1000;
    show(metres);
15. 15.True or false: sorting the scores is processing. (a) False (b) True
16. 16.⚙️ Which line does the processing (works out the answer)?
    line 1: let price = 15; // typed by the user
    line 2: let qty = 2; // typed by the user
    line 3: let total = price * qty;
    line 4: show(total); (a) line 2 (b) line 1 (c) line 3 (d) line 4
17. 17.True or false: a buzz (vibration) is an output. (a) False (b) True
18. 18.🔍 Which is the odd one out? (a) speaking a command (b) tapping a button (c) taking a photo (d) a result on screen
19. 19.True or false: a beep sound is an output. (a) True (b) False
20. 20.🔍 Which is the odd one out? (a) tapping a button (b) checking a password (c) sorting the scores (d) working out a tip
21. 21.🔍 Which is the odd one out? (a) a result on screen (b) a pop-up message (c) taking a photo (d) a beep sound
22. 22.⚙️ What number does this app show?
    let km = 14; // typed by the user
    let metres = km * 1000;
    show(metres);
23. 23.True or false: checking a password is an input. (a) False (b) True
24. 24.True or false: sorting the scores is an output. (a) False (b) True
25. 25.Which of these is an input? (a) speaking a command (b) a beep sound (c) sorting the scores (d) a buzz (vibration)
26. 26.⚙️ In an app, is a buzz (vibration) an input, processing or an output? (a) processing (b) input (c) output
27. 27.True or false: checking a password is processing. (a) True (b) False
28. 28.⚙️ What number does this app show?
    let price = 40; // typed by the user
    let qty = 5; // typed by the user
    let total = price * qty;
    show(total);
29. 29.⚙️ What number does this app show?
    let price = 140; // typed by the user
    let off = 20; // typed by the user
    let pay = price - off;
    show(pay);
30. 30.⚙️ What number does this app show?
    let price = 180; // typed by the user
    let off = 40; // typed by the user
    let pay = price - off;
    show(pay);
31. 31.⚙️ Which line does the processing (works out the answer)?
    line 1: let price = 140; // typed by the user
    line 2: let off = 20; // typed by the user
    line 3: let pay = price - off;
    line 4: show(pay); (a) line 4 (b) line 3 (c) line 1 (d) line 2
32. 32.⚙️ In an app, is a pop-up message an input, processing or an output? (a) processing (b) input (c) output
33. 33.⚙️ In an app, is sorting the scores an input, processing or an output? (a) input (b) processing (c) output
34. 34.⚙️ In an app, is adding up a bill an input, processing or an output? (a) output (b) input (c) processing
35. 35.True or false: a result on screen is processing. (a) False (b) True
36. 36.⚙️ What number does this app show?
    let price = 230; // typed by the user
    let off = 20; // typed by the user
    let pay = price - off;
    show(pay);
37. 37.⚙️ What number does this app show?
    let price = 60; // typed by the user
    let qty = 2; // typed by the user
    let total = price * qty;
    show(total);
38. 38.⚙️ Which line does the processing (works out the answer)?
    line 1: let price = 300; // typed by the user
    line 2: let off = 10; // typed by the user
    line 3: let pay = price - off;
    line 4: show(pay); (a) line 1 (b) line 4 (c) line 3 (d) line 2
39. 39.⚙️ What number does this app show?
    let price = 20; // typed by the user
    let qty = 4; // typed by the user
    let total = price * qty;
    show(total);
40. 40.🔍 Which is the odd one out? (a) speaking a command (b) typing your age (c) working out a tip (d) taking a photo

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