Is there any purpose of x in this question? Also does the box signifies anything?

Now if 3r is odd, then it means r must be odd as well. So sequentially, it would be 1,3,5,7,9…

and if 5 plus s is odd then s must be even. So, sequentially, it would be 2,4,6,8…

the question does not say to look at r and s in sequential order. So, i thought the answer should be D. But the correct answer is B. So, where did I went wrong?

Hi there. The square just signifies the function. It basically says that if the number is odd, then you get the y=3 and if the number is even then y=6.

I just did the strategy of trying numbers and if 5+s is odd, that means than s is even. For example, s=1, 5+1=6 doesn’t work. s=3 5+3=8 doesn’t work. So s is even, which means than Qb 6.

On the other hand, if you multiply an odd number (r) by another odd number (s), then you get an odd number. This means that r must be odd. So Qa is 3.

3<6, correct answer b.

Hopefully this helps you!