Question 1187979: The distribution of head circumference for full term newborn female infants is approximately normal with a mean of 33.8 cm and a standard deviation of 1.2 cm.
For full term newborn female infants, determine the head circumference of a female infant such that 75% of the female infants have their head circumferences less than this female infant. Enter your answer using one decimal place.
I know I have to use the formula x=mean + z(SD) but idk how to find the z score...
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! You can use the table to find the z-score by looking under the probability of ".7500" the 75th percentile, which is what the question means.
Also on calculator for 2ndVARS 3invnorm (0.75,0,1) ENTER or +0.67
z=(x-mean)/sd
0.67=(x-33.8)/1.2
0.80=x-33.8
x=34.6 cm
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