Question

В лотерее учавствуют 100+ 10 билетов, из которых 10 — выигрышные. Куплен один билет. Какова вероятность того, что он выигрышный? Найти вероятность того, что при покупке двух (трёх) билетов, все они окажутся выигрышными.

Answer 1

При покупке одного билета вероятность то что он выигрышный около 1%

Answer 2

Probability of Winning with One Ticket

The probability of winning with one ticket can be calculated using the formula:

P(winning with one ticket) = (Number of winning tickets) / (Total number of tickets)

In this case, there are 10 winning tickets out of 100+10, so the probability is:

P(winning with one ticket) = 10 / 110

Probability of Winning with Two or Three Tickets

When buying multiple tickets, the probability of all of them being winning tickets can be calculated by multiplying the individual probabilities of winning for each ticket.

For two tickets: P(both tickets winning) = P(winning with first ticket) * P(winning with second ticket)

For three tickets: P(all three tickets winning) = P(winning with first ticket) * P(winning with second ticket) * P(winning with third ticket)

Given the probability of winning with one ticket, we can use this to calculate the probabilities for two or three tickets.

Calculating the Probabilities

Using the probability of winning with one ticket, we can calculate the probabilities for two and three tickets being winning tickets.

For two tickets: P(both tickets winning) = (10 / 110) * (9 / 109)

For three tickets: P(all three tickets winning) = (10 / 110) * (9 / 109) * (8 / 108)

Let's calculate these probabilities.