Prime factors

Lesson details

Key learning points

1. In this lesson, we will be investigating the properties and definition of prime factors of numbers, and how to calculate them.

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5 Questions

Q1.
What is the definition of a factor?
A number divides into another number leaving a remainder
Correct answer: A number that divides exactly into another number without leaving a remainder
A number that multiplies another number to get another number
Q2.
What is a prime number?
A number that can be divided by even numbers only
Correct answer: A number that can be divided by itself and one only
A number that can be divided by more than two factors
Q3.
Which of these is not a prime number?
11
3
7
Q4.
Which of these is not a factor of 16?
2
4
8
Q5.
Why do square numbers have an odd number of factors?
Correct answer: Because they always have a repeated factor
Because they are even numbers
Because they are odd numbers

5 Questions

Q1.
What is the first prime number?
1
3
5
Q2.
What are the prime factors of 18?
2 and 5
3 and 5
3 and 6
Q3.
What is the 7th prime number?
19
23
7
Q4.
12 written as a product of prime factors is 2 x 2 x 3. What is 30 written using prime factors?
2 + 3 + 5
Correct answer: 2 x 3 x 5
2 x 7
5 x 6
Q5.
Which of the following is not a prime factor of 42?
2
3
7