A package of 10 batteries is checked to determine if there are any dead batteries. Four batteries are checked. If one or more are dead, the package is not sold. What is the probability that the package will
Not be sold if there are actually three dead batteries in the package?
A) $2 / 3$
B) $6 / 7$
C) $5 / 6$
D) $4 / 5$

Question

A package of 10 batteries is checked to determine if there are any dead batteries. Four batteries are checked. If one or more are dead, the package is not sold. What is the probability that the package will
Not be sold if there are actually three dead batteries in the package? 
A) $2 / 3$
B) $6 / 7$
C) $5 / 6$
D) $4 / 5$

Quizplus · Accepted Answer

The probability of selecting a dead battery is 3/10. The probability of not selecting a dead battery is 7/10. The probability of not selecting a dead battery four times in a row is (7/10)^4 = 2401/10000. The probability of selecting at least one dead battery is 1 - (2401/10000) = 7599/10000.

A Package of 10 Batteries Is Checked to Determine If 2/32 / 32/3

A Package of 10 Batteries Is Checked to Determine If $2 / 3$