[amp_mcq option1=”6″ option2=”2″ option3=”9″ option4=”3″ correct=”option3″]
The answer is 3.
The missing number is the number that, when added to the other two numbers, gives a multiple of 9.
In this case, 2 and 6 are both multiples of 3, so the missing number must also be a multiple of 3. The only answer choice that is a multiple of 3 is 3.
Therefore, the missing number is 3.