The times that cars took to refuel at a busy service station are normally distributed with mean 3
minutes and a standard deviation of 0.5 minutes. What is the probability that a car will take
(a) more than 4 minutes to refuel,
(b) not more than 2 minutes to refuel,
"\\mu= 3 \\\\\n\n\\sigma = 0.5"
(a)
"P(X>4) = 1 -P(X<4) \\\\\n\n= 1 -P(Z< \\frac{4-3}{0.5}) \\\\\n\n= 1 -P(Z< 2) \\\\\n\n= 1 -0.9772\\\\\n\n= 0.0228"
(b)
"P(X<2) = P(Z< \\frac{2-3}{0.5}) \\\\\n\n= P(Z< -2) \\\\\n\n= 0.02275"
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