Question

Find the smallest number which is divisible by the first four prime numbers. What is the highest common factor of the first four prime numbers? [3 MARKS]

Answer 1

Smallest Number: 1 Mark
Highest Common factor: 2 Marks

The first four prime numbers are 2, 3, 5, 7.
1 is neither a prime nor a composite number so we will not include that.
Now, all these numbers are prime numbers, so the smallest number possible which is a factor of these numbers is the lowest common multiple of these numbers.
Since these are all prime numbers, their lowest common multiple is the product of these numbers, which is:
2 $\times$ 3 $\times$ 5 $\times$ 7 = 210
Hence, 210 is the required number.

The given numbers are prime numbers, so all of them will have the highest common factor equal to 1.