Question on probability

Q. The probability that Nike will get Cricket team contract is 2/3 and the probability that Nike will get Hockey team contract is 5/9. If the probability of getting at least one contract is 4/5, what is the probability of getting both the contract? a. 19/45 b. 13/45 c. 12/35 d. 11/23

Probability (Marbles)

Hello all, Please help me solving this problem. A box contains fewer than 10 marbles. If you reach to the box and randomly pull out 2 marbles one after the other, without replacing them you have a 50 percent chance of getting 2 blue marbles. How many blue marbles are there in the box? Thanks in Advance.

Unsolved Probability Questions

The following questions are from arun sharma and no hint/solution is provided in the book
So Please explain how to solve them

Q1. A fair coin is tossed 10 times. Find the probability that two heads do not occur consecutively?
a. 1/2^4
a. 1/2^3
c. 1/2^5
d. None of these

Q2. The probability that a contractor will get a plumbing contract is 2/3 and the probability that he will get an electric contract is 5/9. If the probability of getting at least one contract is 4/5, what is the probability that he will get both the contracts?
a. 19/45
b. 13/45
c. 12/35
d. 11/23

Q3. Three faces of a dice are yellow, two faces are red and one face is blue. The dice is tossed three times. Find the probability that the colors yellow, red and blue appear in first, second and third toss respectively.
a. 1/18
b. 1/12
c. 1/9
d. 1/36

Q4. A bag contain 15 tickets numbered 1 to 15. A ticket is drawn and replaced. Then one more ticket is drawn and replaced. The probability that first number drawn is even and second is odd is
a. 56/225
b. 26/578
c. 57/289
d. None of these

Thanks in advance

probability question

please solve the following questions

Q1. A box contains 6 red balls, 7 green balls and 5 blue balls. Each ball is of a different size. The probability that the red ball selected is the smallest red ball is:
a. 1/18

b. 1/3

c. 1/6

d. 2/3

 

Q2. There are 50 ten paise coins placed on a table. Six of these shows tails and four shows heads. A coin is chosen at random and fliped(not tossed). This operation is performed seven times. One of these coins is then covered. Of the remaining nine conins, five shows tails and four shows heads. The covered coin shows

a. A head

b. A tail

c. More likely a head

d. More likely a tail