2nd Year Blog Homework 1

To be completed neatly in your books due on Monday 22nd Sept. TOTAL 22 marks

1. Write down all the prime numbers less than 30

[3 marks]

2. True or false: There are no even prime numbers. Explain your answer

[2 marks]

3. Draw prime factor trees for

1. 120
2. 51
3. 216

[6 marks]

4. Which primes make up the composite number 78?

[2 marks]

5.

1. Write down the first 10 multiples of 15
2. Write down the first 10 multiples of 12
3. Using the parts above find the lowest common multiple of 15 and 12

[3 marks]

6.

1. Write down all the factors of 96
2. Write down all the factors of 144
3. Using the parts above find the highest common factor of 96 and 144

[3 marks]

7. A number is written down but the last digit has been blurred and cannot be read. The number is 1,275,03x where x is the missing digit. We know that the number is divisible by three, what could the value of x be (there are several possibilities)?

[2 marks]

8. Explain why 1 is not a prime number

[1 marks]