SOLUTION: An unfair coin has probability p of landing heads up on a single flip, where 0 < p < 1. The coin is tossed seven times, and the probability that the coin lands heads up exactly t

Algebra.Com
Question 1192893: An unfair coin has probability p of landing heads up on a single flip, where
0 < p < 1. The coin is tossed seven times, and the probability that the coin lands
heads up exactly twice is equal to the probability that the coin lands heads up
exactly three times. What is the value of p? Express your answer as a common
fraction.

Can I get help on this please? Trying to understand how to solve this? Thank you for your help and time.

Answer by greenestamps(13198)   (Show Source): You can put this solution on YOUR website!


The probability of heads is p; the probability of tails is (1-p).

The probability of getting 2 heads on 7 flips is .

The probability of getting 3 heads on 7 flips is .

The probabilities of 2 or 3 heads are the same:










ANSWER: p=3/8


RELATED QUESTIONS

An unfair coin has a probability 0.6 of landing heads. The coin is tossed four times.... (answered by jim_thompson5910)
An unfair coin has probability 0.3 of landing heads. The coin is tossed six times. What... (answered by greenestamps)
A fair coin is tossed 100 times, landing 59 times on tails, and 41 times on heads. What... (answered by Edwin McCravy,Alan3354)
A fair coin is tossed 100 times, landing 59 times on tails, and 41 times on heads. What... (answered by Fombitz)
A certain unfair coin lands on heads 1/3 of the time. The coin is tossed 5 times. Finds... (answered by swincher4391)
You flip a coin three times. What is the probability of it landing on heads on the third... (answered by Fombitz)
an unfair coin will turn up heads 4 out of 5 times (i.e. P(heads)=0.8). what is the... (answered by sudhanshu_kmr)
An unfair coin has a probability 𝑝 = 0.13 of landing on heads when flipped.... (answered by stanbon)
I need help. Thank you. A biased coin has a 70 % chance of landing on heads. The coin... (answered by greenestamps)