Situation

$36$ students complete a pre$-$test for $36$ students on finance terms. The class then covers three

chapters in a finance book. The $36$ students then take an exam on the three chapters. Which t$-$test

should the company use to determine if the pre$-$test and exam cores are significantly different after

learning the materials in the three chapters?

A company wants to increase sales. It has created a new website layout and wants to determine if it

significantly increases sales revenue. It uses $\frac{A}{B}$ testing where half of the website users use the current

website $($user group A$)$ and half of the website users use the new website $($user group B$).$ Which $t-$test

should the company use to determine if sales revenues are significantly different between user group $A$

and user group B $?$

A company manufactures organic dishwashing soap. Each recyclable glass bottle is supposed to

weigh $0\mathrm{.}5$ pounds after the product has been poured into the bottle and capped. The operations manager

wants to make sure that the machines are properly filling the bottles. Which t$-$test should the operations

manager use to test whether a random sample of bottles are not underfilled or overfilled?

A house painting company wants to determine if a new organic, low$-$VOC paint is more durable than

the paint it is currently using on house siding. The company gathers $100$ pieces of house siding. It paints

half of each siding with its current paint, and the other half of each siding with the new paint. The sidings

are then subjected to weather testing and paint durability scores are collected for each side of the siding.

Which t$-$test should the company use to test whether the new paint is significantly more durable than the

current paint?

A company has $10,000$ customers in its customer relationship management system. The company

decides to email customers a discount code with the goal of increasing sales. The company creates two

versions of the email:

$5,000$ receive Version A email: Offer ends on Saturday. Use the code "GIFT" for a $10\%$ discount.

$5,000$ receive Version B email: Limited stockl Use the code "FORYOU" for a $10\%$ discount.

Which $t-$test should the company use to determine if sales revenues are significantly different between

Version A and Version B emails?

A company has an app that customers use to trade stocks. It has set a goal of $1$ minute or less

response time for a live chat with one of its agents. The company randomly selects $500$ live chats from

the prior year. Which $t-$test should the company use to test whether a random sample of wait times are

significantly more than $1$ minute?

The IT department wants to create data analytic solutions for employees less than two weeks after the

request. The IT department randomly selects $50$ requests from the last six months. Which t $-$test should

the company use to test whether a completion times are less than $2$ weeks?

In hopes of increasing productivity, the accounting department has created a robotic process

automation $($RPA$)$ bot to scrape currency conversion rates from the Internet. It wants to compare the time

it takes an accountant to collect the conversion rates versus the bot. The department has the accountant

and the robot each collect $10$ conversion rates each day over the next two months with the associated

completion times. Which $t-$test should the accounting department use to test whether the bot completes

the task significantly faster than the accountant?

The human resource department $($HR$)$ wants to determine if a training program reduces errors

committed by employees. First, HR counts the monthly errors committed by $45$ employees. Then, the

employees complete a two week training course. After the training course, HR counts the errors