Question

One coin in a collection of 65 has two heads. The rest are fair. If a coin, chosen at random from the lot and then tossed, turns up heads 6 times in a row, what is the probability that it is the two-headed coin?

Answer 1

Answer:

P=1/65.

Step-by-step explanation:

We knaow that one coin in a collection of 65 has two heads. If a coin, chosen at random from the lot and then tossed, turns up heads 6 times in a row. We calculate the probability that it is the two-headed coin.

We calculate  the number of possible combinations:

$C_1^{65}=\frac{65!}{1!(65-1)!}=65$

Number of favorable combinations is 1.

Therefore, the probability is

P=1/65.