Factorise the following numbers by division method. Then, express the numbers as the product of their prime factors. a) 36 b) 60 c) 84 d) 99 e) 180

To find the digit in the blank space that makes the number divisible by 11, we use the divisibility rule for 11. This rule states that a number is divisible by 11 if the difference between the sum of its digits at odd places (from the right) and the sum of its digits at even places (from the right) is either 0 or a multiple of 11.

We will assume that the dots represent a single blank digit, as indicated by "the digit" (singular) in the question.

• a) 27.......3 Let the blank digit be $x$. The number is $27x3$. Step