weight of eggs 95% confidence level n=47 x 1.44 oz and sigma 0.39oz

Question

weight of eggs 95%confidence; n=47 x with a line over it =1.44oz sigma 0.39oz

Answer 1

mean=x̄=1.44oz, σ (population standard deviation)=0.39oz.

If this is a sample we need to find s=σ/√n=0.39/√47=0.057 approx.

The confidence interval is 95% which means 2.5% for each of the tails of the distribution. The Z-score we use is that corresponding to 97.5%=1.96.

Z=(X-1.44)/0.057=1.96, X=1.44+0.112=1.552 (high), X=1.44-0.112=1.328 (low).

We would expect the eggs to weigh between about 1.33 and 1.55 ounces.