The Manager of a Self-Serve Frozen Yogurt Shop, Purple Pear $4.5 \pm 2.228\left(\frac{0.25}{\sqrt{10}}\right)$

Multiple Choice

The manager of a self-serve frozen yogurt shop, Purple Pear, knows that customers swirl different amounts of the creamy concoction into their cups. She samples cups from 10 costumers she believes to be representative of the customers and weighs the cups, finding a mean of 4.5 ounces and standard deviation of 0.25 ounces. Assuming these cups of frozen yogurt can be considered a random sample of all cups of frozen yogurt which of the following formulas gives a 95%
Confidence interval for the mean weight of all cups of frozen yogurt?

A) $4.5 \pm 2.228\left(\frac{0.25}{\sqrt{10}}\right)$

B) $4.5 \pm 2.228\left(\frac{0.25}{\sqrt{9}}\right)$

C) $4.5 \pm 2.262\left(\frac{0.25}{\sqrt{9}}\right)$

D) $4.5 \pm 2.262\left(\frac{0.25}{\sqrt{10}}\right)$

E) $4.5 \pm 1.969\left(\frac{0.25}{\sqrt{10}}\right)$