# 09 - Yr7 & 8 - Assessment (30 min) MCQ & Short Ans

1. Decimal (Base 10) is the only number system in the world.

TRUE

FALSE

2. The ancient Mayan civilisation used the following number system (see image below). This is a ___________________ number system. base 10

base 20

base 15

base 19

3. Binary is a __________ number system.

base 2

base 0 and 1

base 1

base 0

4. In Binary you can create any number in the world using ___________________.

just two digits, 0 and 1

just four digits, 0,1,2,3

just the number 0, which can be placed next to any other number

just ten digits, 0,1,2,3,4,5,6,7,8,9

5. Why do computers use Binary? (Why is it that Binary is the foundational language for computer science and computers?)

6. Convert the Denary (Decimal) number 3 into Binary. Use two bits in your answer. (1 mark)

7. Binary additon is similar in some ways but different from the sort of addition we do with decimal numbers. Using Binary addition what is 1+0? (1 mark)

8. In Binary addition what is 1+1? Write the result and mention what number is carried over as well. E.g. 1 carry 1. (2 marks)

9. In Binary addition what is 1+1+1? What goes in a) and what goes in b). Write your answer in this format: a=?, b=? (2 marks) 10. In the following example, what are the values of a and b? Write your answer in this format: a=?, b=? (1 mark) 11. In a bitmap image, it is possible to store letters in a table, where each letter represents a colour. Explain how a bitmap image is stored in a computer (2 marks)

12. Explain how reducing the number of colours in an image can reduce its file size. (2 marks)

13. If you want a greater range of colours and tones, it would be better to use 2 bits. A greater number of bits would result in blurring.

TRUE

FALSE

14. According to the following chart, using 3 bits would allow you ___________________. 12 colours

8 colours

3 colours

3 x 2 colours = 12 colours

15. In pixel __________, the term _____________ refers to the total number of count of pixels in an digital image

colour depth

resolution

pixolatton

colouration

16. Which of the following (types of image) is the image on the left likely to be? bitmap

graphic

pixelo

vector

17. What is the following Binary number in Decimal?
`10000000`

18. What is the following Binary number in Decimal?
`11111111`

255

129

200

356

19. Neriah has created a number system. In it, 0 = *; 1 = & and 2 = @. Her number system is a base 3 system. What is the following number in Decimal? **@?