Question

You measure 47 dogs' weights, and find they have a mean weight of 57 ounces. Assume the population standard deviation is 2.9 ounces. Based on this, determine the point estimate and margin of error for a 99% confidence interval for the true population mean dog weight. Give your answers as decimals, to two places

Answer 1

Solution :

Given that,

Point estimate = sample mean = = 57

Population standard deviation =    = 2.9
Sample size = n =47

At 99% confidence level the z is ,

  = 1 - 99% = 1 - 0.99 = 0.01

/ 2 = 0.01 / 2 = 0.005

Z_/2 = Z_0.005 = 2.576   ( Using z table )

Margin of error = E = Z_/2* ( /n)

= 2.576* ( 2.9/ 47)

= 1.09