![\begin{gathered} We\text{ are given that x is N\lparen43,12\rparen} \\ To\text{ find the probability that the shopper is in the store between 33 and 66 minutes, we will calculate the Z scores} \\ at\text{ 33 and 66 minutes.} \\ Z\text{ =}(33-43)/(12) \\ \text{ =-0.833} \\ P\text{ = 0.336} \\ and \\ Z\text{ = }(66-43)/(12) \\ =1.92 \\ P\text{ = 0.9726} \\ To\text{ find the probability inbetween we minus one probability from another.} \\ P\text{ = 0.9726 0.336} \\ =\text{ 0.6366} \end{gathered}]()
We are given that x N(43,12)
To find the probability that the shopper is in the store between 33 and 66 minutes, we will calculate the Z score at each of these times.
Z = 33-43/12 = -0.833
P = 0.336
Z = 66-43/12 = 1.92
P = 0.9726
To find the probability inbetween these values we will minus one from another
P = 0.9726 -0.336
= 0.6366
Answer to part a). P = 0.6366
b) We will calculate the z score at 39 minutes:
Z = (39-43)/12 = -0.33
P(x<39) = 0.3707. The Z table gives us the probability that ZThe probability that the shopper stays in the shop for more that 39 minutes is 1 minus this probability.
1-0.3707 = 0.6293
Answer to part b). = 0.6293