An unfair coin is tossed twice. The probability of heads is 3 times the probability of tails. What is the probability that at least one head is flipped?


closed as off-topic by user223391, wythagoras, Simon S, Dilip Sarwate, ronno Jul 2 '15 at 8:35

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Community, wythagoras, Simon S, Dilip Sarwate, ronno
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 2
    $\begingroup$ What have you tried? In its current status, your question probably will be downvoted and closed, meaning that you won't get an answer. By providing your attempt, we can provide better help and you can learn more. $\endgroup$ – wythagoras Jul 1 '15 at 18:54

If I'm interpreting your question correctly, if the probability of heads is three times the probability of tails, then we have $P(\text{heads}) = 3/4$ and $P(\text{tails}) = 1/4$.

Because the probability of getting no heads is $1/4 \cdot 1/4 = 1/16$, the probability of getting at least one head is $15/16$.

  • $\begingroup$ yap its right answer thnx $\endgroup$ – iftikhar ali Jul 2 '15 at 20:19

Not the answer you're looking for? Browse other questions tagged or ask your own question.