Looking at the question we can see that it says:

We should know what these symbols mean:
stands for something less than the other, for example:
We can say that 2 is less than 5 so in a symbolic form it can be written as,
Similarly,
stands for something greater than the other, for example:
We can say that 7 is greater than 5, in a symbolic form it can be written as,

So here,
means that, 42153 is greater than 35214.
We need to find the probability of the card chosen at random is yellow or brown.
So, since there are 3 yellow cards and 7 brown cards, the total numbers of cards that are yellow or brown is:

Now, the probability that the chosen card is yellow or brown can be found by dividing the above value by the total number of cards in the box.
The total number of cards in the box is:

Thus, that probability is given by:

Therefore, the answer is:
The reflection point P' would be (-6, 8)