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a paint-store chain produces and sells latex and semigloss paint .Based on long-range sales, the probability that a customer will purchase latex paint is 0.75. Of those that purchase latex paint , 60% also purchase rollers. But only 30% of semigloss paint buyers purchase rollers . A randomly selected buyer purchases a roller and a can of paint . What is the probability that the paint is latex?

ابي حله بالتفصيل

s

a town has 2 fire engines operating independently . The probability that a specific engine is available when needed is 0.96

a- What is the probability that neither is available when needed?

b- What is the probability that a fire engine is available when needed?

customers buy latex paint and a roller= .75 * .60 =.45

customers buy semigloss and a roller= .25 * .30 = 0.075

so if a customer purchases a roller the probability that the can is paint lates as follow:

probability= .45/(.45+0.075) = .8571

85.71%

إن كنت تتسال من اين اتت (25.) هي كالتالي

1-0.75=

.25