Our department store is having a sale on personal computers, of which three are

Question

Our department store is having a sale on personal computers, of which three are in stock (no rain checks). There is a certain probability of selling none. The probability of selling one is twice as great as the probability of selling none. The probability of selling two is three times the probability of selling none. Finally, the probability of selling all the personal computers is four times as great as the probability of selling none. Using the above information, what is the probability of selling all three personal computers? Hint: Let the probability of selling none equal x.

Explanation / Answer

Let probablity of selling none equal,P(0)= x

So, probablity of selling one is P(1)=2x

Probality of selling two is, P(2)=3x

Probability of selling all,P(3)=4x

The probalities shoudl add up to 1

x+2x+3x+4x=1

x=1/10

So, probality of selling all three =4/10=2/5

Related Questions

Navigate

• Browse (All)
• Browse O
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.