Answer: The probability is 0.4
Step-by-step explanation:
Since the time taken to assemble a car in a certain plant is a random variable having a normal distribution, we would apply the formula for normal distribution which is expressed as
z = (x - ”)/Ï
Where
x = time taken to assemble cars
” = mean time
Ï = standard deviation
From the information given,
” = 20 hours
Ï = 2 hours
We want to find the probability that a car can be assembled at this plant in a period of time less than 19.5 hours. It is expressed as
P(x < 19.5) = 1 - P(x †19.5)
For x = 19.5
z = (19.5 - 20)/2 = - 0.25
Looking at the normal distribution table, the probability corresponding to the z score is 0.4
