Question

Question

A candy manufacturer sells bags of chocolate treats that are supposed to be half dark chocolate and half milk chocolate. The CEO opened a bag of the chocolate treats and told his factory supervisor that he thinks that the types of chocolate are not evenly split in the bag. The supervisor randomly selected several bags, examined 200 of the chocolates, and found that 55% of the 200 chocolates he examined were dark chocolate.

Use a TI-83, TI-83 plus, or TI-84 calculator to test whether the true proportion of dark chocolates is different from 50%. Identify the p-value, rounding to three decimal places.

PLEASE SHOW THE STEPS ON THAT CALCULATOR, THANK YOU

Answer 1

We have given P = 0.50 , P^ = 0.55 , n = 200

We know that p^ = x / n Hence we get x = p^ * n = 0.55 *200 = 110

I will give you the command for Ti-84 plus calculator.

1) Press STAT ------> then go to TESTS ------> select 5 option 1-PropZTest

P0= 0.5

x = 110

n = 200

Prop: P0 and hit the calculate button.

You will get the output as -

We get-  P value = 0.157

Decision rule :

If p value aplha reject H0.

If p value > alpha Fail to reject H0.

Here P value ( 0.157) > alpha (0.05) Hence we fail to reject H0.

conclusion : The true proportion of dark chocolates is NOT different from 50%.

Hope this will help you. Thank you :)