11-plus Maths | Properties of numbers

Back to Maths

Maths Quiz - Properties of Numbers (Difficult) (Questions)

Some numbers are prime numbers - some numbers have other properties. In this Maths quiz, you will get some more practice in dealing with the properties of numbers. See how well you can do to improve your 11-plus grades.

As you continue through school and maths lessons, you'll learn a lot more about numbers. For now, we are dealing with the easy stuff, so make sure you get 10 out of 10 in this quiz and our others on properties of numbers.

If you choose to go further with maths when you leave school, no doubt you will come across some strange terms for numbers. Most likely, you've heard of infinity ~ this means without end ~ and numbers go on forever. Saying this, you will learn about Graham's number, TREE(3) and a googolplex!

Getting back to this quiz, we're counting on you getting a good score!

What is the smallest prime number?

[ ]	2
[ ]	1
[ ]	0
[ ]	-1

Which of the following statements is wrong?

[ ]	Two is an even number and a prime number
[ ]	Other than the number 2, there are no even prime numbers
[ ]	If you add two odd numbers, you get another odd number
[ ]	If you add two even numbers, you get another even number

Which number is the odd man out: 49, 15, 41, 9?

[ ]	9
[ ]	15
[ ]	49
[ ]	41

Which number is the odd man out: 64, 32, 144, 100?

[ ]	144
[ ]	64
[ ]	100
[ ]	32

Which number is the odd man out: 71, 17, 11, 39?

[ ]	11
[ ]	17
[ ]	39
[ ]	71

Which two prime numbers have to be added together to give 38?

[ ]	11 + 27
[ ]	19 + 19
[ ]	23 + 15
[ ]	29 + 9

Which of the following statements is wrong?

[ ]	If a number is divisible by 9, then it is divisible by 3
[ ]	If you add two prime numbers together, you get another prime number
[ ]	If you subtract 1 from an even number, you get an odd number
[ ]	There are four prime numbers between 1 and 10

How many prime numbers are there between 1 and 30?

[ ]	10
[ ]	12
[ ]	11
[ ]	9

Which of the following statements is wrong?

[ ]	13 is an odd number
[ ]	13 × 13 = 159
[ ]	13 is a prime number
[ ]	13 is the sixth smallest prime number

10.

For those of you with stamina: How many prime numbers are there between 1 and 100 inclusive?

[ ]	29
[ ]	26
[ ]	27
[ ]	25

Maths Quiz - Properties of Numbers (Difficult) (Answers)

What is the smallest prime number?

[x]	2
[ ]	1
[ ]	0
[ ]	-1

A prime number is a positive whole number that is only divisible by 1 and itself but does not include the number 1, e.g. 2, 3, 17, 41

Which of the following statements is wrong?

[ ]	Two is an even number and a prime number
[ ]	Other than the number 2, there are no even prime numbers
[x]	If you add two odd numbers, you get another odd number
[ ]	If you add two even numbers, you get another even number

7 + 5 = 12 which is not odd. If you want to show that a statement is not always true, find one example that shows it is wrong - like we did here

Which number is the odd man out: 49, 15, 41, 9?

[ ]	9
[ ]	15
[ ]	49
[x]	41

They are all odd, but 41 is also a prime number: a prime number is a positive whole number that is only divisible by 1 and itself but does not include the number 1

Which number is the odd man out: 64, 32, 144, 100?

[ ]	144
[ ]	64
[ ]	100
[x]	32

They are all even numbers, but 32 is not a square number. A square number (perfect square) is a number formed by the multiplication of another number with itself, e.g. 144 = 12 × 12; 64 = 8 × 8; 100 = 10 × 10. Note: 1 × 1 = 1

Which number is the odd man out: 71, 17, 11, 39?

[ ]	11
[ ]	17
[x]	39
[ ]	71

They are all odd numbers, but only 39 is a non prime number: a prime number is a positive whole number that is only divisible by 1 and itself but does not include the number 1

Which two prime numbers have to be added together to give 38?

[ ]	11 + 27
[x]	19 + 19
[ ]	23 + 15
[ ]	29 + 9

This is the only choice that has two prime numbers

Which of the following statements is wrong?

[ ]	If a number is divisible by 9, then it is divisible by 3
[x]	If you add two prime numbers together, you get another prime number
[ ]	If you subtract 1 from an even number, you get an odd number
[ ]	There are four prime numbers between 1 and 10

11 + 7 = 18 which is not a prime number. If you want to show that a statement is not always true, find one example that shows it is wrong - like we did here

How many prime numbers are there between 1 and 30?

[x]	10
[ ]	12
[ ]	11
[ ]	9

Here they are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29

Which of the following statements is wrong?

[ ]	13 is an odd number
[x]	13 × 13 = 159
[ ]	13 is a prime number
[ ]	13 is the sixth smallest prime number

13 × 13 = 169! D'oh! By the way, just because 13 is odd, this doesn't prevent it from being a prime number too

10.

For those of you with stamina: How many prime numbers are there between 1 and 100 inclusive?

[ ]	29
[ ]	26
[ ]	27
[x]	25

Well done those of you who bothered to do this question. The rest of you - do it later. There are 25 prime numbers between 1 and 100. Here they are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89 and 97. Phew! Does anyone want to find out how many prime numbers there are between 1 and 1,000 inclusive? Just joking! Here's the answer anyway: 168 prime numbers. I wonder if your teacher knows that? By the way, prime numbers are a big thing in higher maths