Question

I want an explanation for number 7 please

Answer 1

So for number 7, instead of being able to say that the probability is out of 10 because there are 10 cards, you actually need to draw a probability tree and say that the first time you take a card out, the probability of getting an even number is 5/10, but the second time, one card is missing so it is (if the card was an even number first) 4/9 and (if the card was an odd number first) 5/9. Because you want the probability of two even numbers, you would need to say that the first one was even and so was the second, and then you multiply. So, 5/10 × 4/9 = 20/90, which can simplify to 2/9. I hope this helps! Let me know if you need more explanation or anything :)