Answers

These are some suggested answers for Hello Ruby: Adventures in Coding as well as Hello Ruby: Journey Inside the Computer

Hello Ruby: Journey Inside the Computer

These answers are not necessarily the only right ones. Remember, there are usually many ways to solve problems!

Exercise 2

  • Software: cursor, game, word processor and chat application

  • Hardware: phone, game console, printer and mouse

  • Pairs (for example): cursor and mouse, game and game console, printer and word processor, chat application and phone

Exercise 3

Use your imagination! Almost all of the objects are computers, in some way or another. The important thing here is to discuss what a computer is and is not, what computers can do and how technology changes our everyday objects. Examples:

Exercise 6:

Again - many different answers. Humans are usually better at creative tasks, things that require negotiation with other humans or adaptation. Computers can repeat things over and over again, they like tasks with routine, they can only do things that are programmable, and don't have emotions!

Exercise 7:

  • Input devices: mouse, keyboard, microphone, camera

  • Output devices: earphones, printer, 3D printer, screen

  • Both: touch screen, temperature sensor

Exercise 10

Pairs are:

  • Smell and nose

  • Sight and eyes

  • Hearing and ears

  • Taste and mouth

  • Touch and skin

Exercise 11

  • Second exercise. Add three balls.

  • Third exercise: Input starts with six balls.

  • Fourth exercise: The story is printed

  • Fifth exercise: The pressure sensor recognises if someone is sitting in the chair and sends a message to the computer. Out comes a beep beep beep noise.

  • Sixth exercise: The light sensor recognises the change in the amount of light (whether it´s morning or evening). The moisture sensore recognises how moist the ground is and whether it should be watered. The garden is watered and output is happy plants.

Exercise 13

From left to right: GPU, ROM, Mass Storage, CPU, RAM

Exercise 15

Sudoku

Exercise 18

  • Wireless mouse - Bluetooth

  • Power chord - Mini USB

  • Headphones - AUX

  • Camera - USB

Exercise 20

  • One paragraph of text - one kilobyte

  • Movie - one gigapyte

  • Letter A - one byte

  • Vacation photo - one megabyte

Exercise 22

AND gate

AND gate is pretty picky: it only approves answers that are both true.

  1. The first gate is telling the truth. 1

  2. The second gate is not telling the truth. It´s false. 0

  3. The third gate is not telliong the truth. 0

  4. The fourth gate is not telling the truth. 0

OR gate

OR gate is more relaxed: it approves answers where either of the statements are true.

  1. The first gate is not telling the truth. It´s false. 0

  2. TThe second gate is telling the truth. 1

  3. The third gate is telling the truth. 1

  4. The fourth gate is telling the truth. 1

NOT gate

NOT gate always reverses the answer.

  1. The first gate is telling the truth: it´s not yellow. 1

  2. The second gate is telling the truth: it´s not blue. 1

  3. The third gate is not telling the truth. It is pink. 0

  4. The fourth gate is telling the truth: it is not violet. 1

Truthtables:

AND

True | True | True

True | False | False

False | False | False

False | True | False

OR

False | False | False

False | True | True

False | True | True

False | False | False

NOT

False | True

False | True

True | False

False | True

Hello Ruby: Adventures in Coding

Exercise 1: Bossy Little Ruby

Imagination and mischief is celebrated here! You can gradually make the instructions more and more exact. A few suggestions:

  • Give instructions in the right order.

  • Be specific on what you call things and how you describe them. A computer won’t understand words like some, little bit, a lot..

  • Write down instructions for various situations. A computer needs to have instructions available for all sorts of situations.

  • Make sure to tell when to start and finish an activity! Computer won’t stop pouring the milk, unless you explicitly tell it to.

Exercise 2: The Builder

  • The nose of the bird is missing.

  • The half-moon shaped piece is extra.

  • The yellow arc, the green dot and the yellow bar are extra.

Exercise 3: Ruby's Outfit Rules

  • Monday: outfit three

  • Tuesday: outfit two

  • Wednesday: outfit one (a dress)

  • Thursday: outfit five

  • Friday: outfit four.

You can also try coming up with rules that allow Ruby more choices for clothes. Is a crown a hat?

Exercise 4: Dad's Keyboard

In order of the strings: - Fox

  • Ruby

  • Robot

  • Django

  • Penguin

  • Snowleopard

Exercise 5: Ruby's Tea Party

  • Everyone (including Ruby) has a place to sit

  • One cup is pink. Three are yellow.