Question

Determine the secret number: it's a factor of 30, not a prime number, not a multiple of 3, not less than 3. What is the secret number?

Answer 1

It's 3.

Answer 2

10

Answer 3

I think it is important to go through the process of solving this type of question. This is an elimination based question - you have a bunch of options and each provided condition eliminates one or more option.

Let's take the statements one at a time.
1. It's a factor of 30 : Possible options are : 1, 2, 3, 5, 6, 10, 15, 30
2. Not a prime number: so, 1, 2, 3, 5 are out. Possible options remaining: 6, 10, 15, 30
3. Not a multiple of 3: so 6, 15, and 30 are eliminated. Remaining option is 10.

Since 10 is the last remaining option, it must be the answer. Let's check it against the last condition:
4. Not less than 3: Since 10 is greater than 3, 10 is the correct answer.

Answer 4

Thanks Sid! Next time I will explain my answer as you so eloquently did above :)