in the united states, birth weights of newborn babies are approximately normally distributed with a mean of…

in the united states, birth weights of newborn babies are approximately normally distributed with a mean of $mu = 3,500$ g and a standard deviation of $sigma = 500$ g. what percent of babies born in the united states are classified as having a low birth weight (< 2,500 g)? explain how you got your answer.

in the united states, birth weights of newborn babies are approximately normally distributed with a mean of $mu = 3,500$ g and a standard deviation of $sigma = 500$ g. what percent of babies born in the united states are classified as having a low birth weight (< 2,500 g)? explain how you got your answer.

Answer

Explanation:

Step1: Calculate the z - score

The z - score formula is $z=\frac{x-\mu}{\sigma}$, where $x = 2500$, $\mu=3500$ and $\sigma = 500$. $z=\frac{2500 - 3500}{500}=\frac{- 1000}{500}=-2$

Step2: Find the proportion from the standard normal table

The standard - normal table gives the cumulative probability $P(Z\lt z)$. Looking up $z=-2$ in the standard - normal table, we find that $P(Z\lt - 2)=0.0228$.

Answer:

2.28%