Question

Birth weights of full-term babies in a certain area are normally distributed with mean 7.13 pounds and standard deviation 1.29 pounds. A newborn weighing 5.5 pounds or less is a low-weight baby. What is the probability that a randomly selected newborn is low-weight? Use the appropriate applet. Enter a number in decimal form, e.g. 0.68, not 68 or 68%.

Answer 1

Answer: probability that a randomly selected newborn is low-weight is 0.1038

Explanation:

Since Birth weights of full-term babies in a certain area are normally distributed m, we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = birth weights of full-term babies.

µ = mean weight

σ = standard deviation

From the information given,

µ = 7.13 pounds

σ = 1.29 pounds

The probability that a randomly selected newborn is low-weight is expressed as

P(x ≤ 5.5)

For x = 5.5

z = (5.5 - 7.13)/1.29 = - 1.26

Looking at the normal distribution table, the probability corresponding to the z score is 0.1038

P(x ≤ 5.5) = 0.1038