The probability of getting 9 cards of the same suit in one hand at a game of bridge is:
4 × ¹³C₉ × ³⁹C₄ / ⁵²C₁₃
Total hands: 13 cards chosen from 52, i.e. \(\binom{52}{13}\).
Favourable hands (exactly 9 of one suit):
Choose the suit in \(\binom{4}{1}=4\) ways, pick 9 of its 13 cards in \(\binom{13}{9}\) ways, and fill the remaining 4 cards from the other 39 cards in \(\binom{39}{4}\) ways.
\[P = \dfrac{4 \times \binom{13}{9} \times \binom{39}{4}}{\binom{52}{13}}\]
This matches option (1).
Five persons A, B, C, D and E occupy seats in a row at random. The probability that A and B sit next to each other is:
The chance that a software engineer will debug an error X correctly is 80%. The chance that software with the error X will crash after the correct debugging is 30%. The chance of crash of the software by wrong debugging is 70%. A software with the error X crashed. The probability that its error was debugged correctly is:
A closet contains 8 pairs of shoes. If 4 shoes are chosen at random, then the probability that all the four shoes are of the same type (left or right) is:
The probability that an urn containing 5 balls contains only white balls if the first two balls drawn from it were found to be white is:
At a round table, n persons are seated on n chairs. The probability that two friends from same college are sitting next to each other, is:
Let A, B and C be three mutually exclusive and exhaustive events associated with a random experiment. If P (B) = 1.5 P (A) and P (C) = 0.5 P (B), then P (A) is equal to
Five persons A, B, C, D and E occupy seats in a row at random. The probability that A and B sit next to each other is:
A natural number n is chosen from the first 50 natural numbers. What is the probability that \(n+\frac{50}{n}<50 \) ?
If the probability of A to fail in an examination is 0.2 and that for B is 0.3, then, the probability that either A or B fails is:
A problem in Mathematics is given to 3 students A, B and C. If the probability of A solving the problem is \(\dfrac{1}{2}\) and B not solving it is \(\dfrac{1}{4}\) and the whole probability of the problem being solved is \(\dfrac{63}{64}\), then what is the probability of solving it by C?