The 3 digits in the unit period is 817
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:
Speak in English please. I would be more pleased to help if you write in English.
Just search up the name of your worksheet online and then at the end of the name/title,lesson and chapter/unit type in "answer key"
****Equal to one or greater than 1***