Complete Question
Height of Dutch Men. Males in the Netherlands are the tallest, on average, in the world with an average height of 183 centimeters (cm) (BBC News website). Assume that the height of men in the Netherlands is normally distributed with a mean of 183 cm and standard deviation of 10.5 cm.a.What is the probability that a Dutch male is shorter than 175 cm?b.What is the probability that a Dutch male is taller than 195 cm?c.What is the probability that a Dutch male is between 173 and 193 cm?d.Out of a random sample of 1000 Dutch men, how many would we expect to be taller than 190 cm?
Answer:
a. 0.2231
b. 0.1266
c. 0.6591
d. 252 people
Step-by-step explanation:
We solve using the z score formula of
z = (x-μ)/σ, where
x is the raw score
μ is the population mean = 183 cm
σ is the population standard deviation = 10.5 cm
a.What is the probability that a Dutch male is shorter than 175 cm?
This is interpreted as when x < 175 cm
Hence:
z = 175 - 183/10.5
z = -0.7619
Probability value from Z-Table:
P(x<175) = 0.22306
Approximately ≈ 0.2231
b.What is the probability that a Dutch male is taller than 195 cm?
This is interpreted as when x > 195 cm
Hence:
z = 195 - 183/10.5
z = 1.14286
Probability value from Z-Table:
P(x<195) = 0.87345
P(x>195) = 1 - P(x<195) = 0.12655
Approximately ≈ 0.1266
c.What is the probability that a Dutch male is between 173 and 193 cm?
For x = 173
z = 173 - 183/10.5
z = -0.95238
Probability value from Z-Table:
P(x = 173) = 0.17045
For x = 193
Hence:
z = 193 - 183/10.5
z = 0.95238
Probability value from Z-Table:
P(x= 193) = 0.82955
Hence, the probability that a Dutch male is between 173 and 193 cm
P(x = 193) - P(x = 173)
0.82955 - 0.17045
= 0.6591
d.Out of a random sample of 1000 Dutch men, how many would we expect to be taller than 190 cm?
This is interpreted as when x > 190 cm
Hence,
z = 190 - 183/10.5
= 0.66667
Probability value from Z-Table:
P(x<190) = 0.74751
P(x>190) = 1 - P(x<190)
= 0.25249
Therefore, the number of people we would expect to be taller than 190 cm is
Random number of samples × Probability
= 1000 × 0.25249
= 252.49 people
Approximately≈ 252 people