Question

Choose the correct option which shows the prime factorisation of 90.

• A. $2\times 9\times 5$
• B. $2\times 3\times 3\times 5$
• C. $2\times 3\times 15$
• D. $6\times 3\times 5$

Answer 1

The correct option is B

$2\times 3\times 3\times 5$

Prime factorisation is to express a number in terms of the product of prime numbers.
$90=2\times 3\times 3\times 5$