# Lion or virgin

We toss coin, every throw fits lion or a virgin with equal probability 1/2. Determine how much at least we have to make throws that with probability 0.9 lion fell at least once.

Result

n =  4

#### Solution: Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...): Be the first to comment! #### To solve this example are needed these knowledge from mathematics:

Would you like to compute count of combinations?

## Next similar examples:

1. Balls We have n identical balls (numbered 1-n) is selected without replacement. Determine 1) The probability that at least one tensile strength number coincides with the number of balls? 2) Determine the mean and variance of the number of balls, which coincides.
2. Shooters In army regiment are six shooters. The first shooter target hit with a probability of 49%, next with 75%, 41%, 20%, 34%, 63%. Calculate the probability of target hit when shooting all at once.
3. Candies In the box are 12 candies that look the same. Three of them are filled with nougat, five by nuts, four by cream. At least how many candies must Ivan choose to satisfy itself that the selection of two with the same filling? ?
4. Three shooters Three shooters shoot, each one time, on the same target. The first hit the target with a probability of 0.7; second with a probability of 0.8 and a third with a probability of 0.9. What is the probability to hit the target: a) just once b) at least once c
5. Normal distribution GPA The average GPA is 2.78 with a standard deviation of 4.5. What are students in the bottom the 20% having what GPA?
6. Intercept with axis F(x)=log(x+4)-2, what is the x intercept
7. Balls From the urn in which are 7 white balls and 17 red, gradually drag 3-times without replacement. What is the probability that pulls balls are in order: red red red?
8. Cards Suppose that are three cards in the hats. One is red on both sides, one of which is black on both sides, and a third one side red and the second black. We are pulled out of a hat randomly one card and we see that one side of it is red. What is the probabi
9. Cards The player gets 8 cards of 32. What is the probability that it gets a) all 4 aces b) at least 1 ace
10. Today in school There are 9 girls and 11 boys in the class today. What is the probability that Suzan will go to the board today?
11. Lottery Fernando has two lottery tickets each from other lottery. In the first is 973 000 lottery tickets from them wins 687 000, the second has 1425 000 lottery tickets from them wins 1425 000 tickets. What is the probability that at least one Fernando's ticket w
12. Theorem prove We want to prove the sentence: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
13. Log if ?, what is b?
14. Exponential equation In the set R solve the equation: ? After 548 hours decreases the activity of a radioactive substance to 1/9 of the initial value. What is the half-life of the substance? The city has 22,000 residents. How long it is expected to have 25,000 residents if the average annual population growth is 1.4%? Determine the number whose decimal logarithm is -3.8.