Twenty tickets are sold in a raffle which has 2 prize.if u buy 5 tickets ,the probability of winning at least one prize is?

To calculate the probability of winning at least one prize when buying 5 tickets out of 20, we can calculate the probability of not winning any prize and then subtract that from 1.

The probability of not winning any prize with 5 tickets is calculated as follows:
- The probability of not winning a prize with one ticket is (20-2)/20 = 18/20 = 9/10
- The probability of not winning a prize with 5 tickets is (9/10)^5 = 0.59049

Therefore, the probability of winning at least one prize with 5 tickets is:
1 - 0.59049 = 0.40951

So, the probability of winning at least one prize with 5 tickets is approximately 0.40951 or 40.951%.

Step 1: Find the probability of not winning any prize.

To win at least one prize, you must avoid losing all 5 tickets. The probability of losing a single ticket is 18/20 (18 tickets out of 20 do not have a prize).

Step 2: Calculate the probability of losing all 5 tickets.

The probability of losing all 5 tickets is (18/20)^5 = 0.3243.

Step 3: Subtract the probability of losing all 5 tickets from 1 to find the probability of winning at least one prize.

1 - 0.3243 = 0.6757

Therefore, the probability of winning at least one prize if you buy 5 tickets is 0.6757 or 67.57%.