Question

The average birth weight of elephants is 230 pounds. Assume that the distribution of birth weights is Normal with a standard deviation of 50 pounds. Find the birth weight of elephants at the 90th percentile. The birth weight of elephants at the 90th percentile is _____ pounds.

Answer 1

Answer:

294.1 pounds

Step-by-step explanation:

Step 1

We find the z score for 90th percentile

= 1.282

Step 2

We solve using z score formula

z = (x-μ)/σ, where

x is the raw score ??

μ is the population mean = 230 pounds

σ is the population standard deviation= 50 pounds

1.282 = x - 230/50

Cross Multiply

1.282 × 50 = x - 230

64.1 = x - 230

x = 230 + 64.1

x = 294.1 pounds

The birth weight of elephants at the 90th percentile is 294.1 pounds.