Buying and Selling Game Contest #21 (New Business Version) – 30 Hive to be won

in Economics8 months ago

Hi Everyone,


It is great to be back writing posts, making videos and running contests. It has been a very busy few weeks for me, as I have recently moved house. The final week before leaving was tough as there was so much to be done in a short time. The first few weeks at the new house has also been very busy. Several things needed to be done before we could settle in. Check my recent Actifit Report for details.

On my return, I decided to run a Buying and Selling Game contest. This makes sense as I aim to run one of these contests every month and we are running out of time in September. I have several other posts I plan to complete in the coming weeks. These will be focused on economics. I have written very few of these recently, as my time before moving was dedicated to the 7-Week Challenge series.

Welcome to the ‘Buying and Selling’ Game (Business Version)

The Buying and Selling Game series returns with the business version of the game. I introduced the business version in my post/video 'Buying and Selling Game (Business Version) Explanation Video'. The video explains how the game is played and how a winner is determined. The business version was also used for Contest 19 and Challenge 6 of the Economics Challenge series. I recommend that you look at the video as well as the other contests to get a better idea of how to play.

How to play?

The ‘Buying and Selling’ Game (Business Version) involves two simple steps.

  1. Choose the quantity of each good you want to buy or make.
  2. Choose the selling price of each good you bought or made.

All the information you need to know to play the game is provided in the question; i.e. no external research is required as all costs and demand estimates are hypothetical.

All entries must be made in the comments section of this post.

Each account is only permitted one entry.

Objectives of the game

The objective of the game is to make the highest profit from the sale of the goods you have bought or made. If two participants make the exact same profit, the participant that entered first wins.

If nobody makes a profit (i.e. nobody enters the contest or if all participants make a loss), the prize of 30 Hive will be rolled over to the next contest. Therefore, the prize for the next contest will be 60 Hive.

Game assumptions

Each good has 100 potential customers. Each customer can buy up to 6 items of a particular good if he or she values the goods above the selling price (i.e. has a willingness-to-pay higher than the selling price). Each customer is only interested in one type of good. Therefore, selling more types of goods increases the potential number of customers. For examples selling three types of goods grants access to 300 potential customers.

Demand for the goods for each customer is determined using triangle distributions. The question provides the minimum, maximum, and mode willingness-to-pay for each good. Demand is further adjusted for diminishing marginal utility using a fixed percentage adjustment. The demand curve is the summation of demand of all potential customers. See example of triangle distribution below. A sample demand curve is shown later in the post.

Selling Price Distribution


Each customer has diminishing utility (diminishing willingness-to-pay as more goods are bought) for each good. For example, a customer may have a willingness-to-pay of $1.00 for the first item, $0.80 for the second item, $0.60 for the third item, $0.40 for the fourth item, $0.20 for the fifth item, and $0.00 for the sixth item. The question will state this diminishing utility as 20% (i.e. 0.2/1 = 20%), which is applied linearly. If a participant prices the good at $0.50, the customer will buy three items, as the customer values the fourth item below $0.50 (i.e. $0.40).

The business will have overhead costs, which needs to be deducted from the budget before goods can be bought. There are zero transaction and transport costs.

If some goods remain unsold, they will be treated as being wasted, which is equivalent to being sold for $0. This could occur if a participant prices a good too high.

What information is provided?

  • All the goods that can be bought in the game are provided.
  • All costs (i.e. costs to buy/make goods and overhead costs) are provided.
  • Any special purchasing requirements are provided. For example, a good may need to be bought in fixed quantities.

How are the results of the game determined?

A Microsoft Excel Model is used to determine the demand of each good. The costs, quantities bought, quantities sold, and prices will be used to calculate the profits made by each participant. In the results post, the calculation of the demand and profits will be presented in a video.

Contest Prizes

The account with the winning entry will receive 30 Hive and the first 12 entries will be given upvotes. The winner will receive an additional 5 Hive, if he or she obtains a higher profit than the model’s internal estimator.

Let the contest begin

For Contest 21 of the Buying and Selling Game, participants will be running a book shop. Participants will be able to sell three types of book.

  • Non-fiction books
  • Fiction books
  • Children’s books

The participants will only be able to purchase non-fiction books in batches of 10, fiction books in batches of 20, and children’s books in batches of 30. The costs of purchasing each batch, the average cost per book and daily overheads are provided in the tables below.

Cost Information

Note: Budget includes Daily Overhead. If the budget is $1,200 and the daily overhead is $200, there is $1,000 remaining to purchase books.

The parameters to determine demand are provided in the table and graphs below.

Demand Information

Note: The graphs for the triangle distribution are based on the minimum, maximum, and mode prices for the first book a customer buys. The demand curve is adjusted to include diminishing utility expressed in the last column of the table. This will affect the elasticity of demand.

It has been assumed each type of book has 100 potential customers. Each customer will potentially buy a maximum of 6 books. Therefore, it is possible a maximum of 600 of each book could be sold. The Figure below contains a sample of a possible demand curve that could be generated by the model using the parameters described in this question.

Possible Demand Curve

Note: Sample demand curve for fiction books. Actual demand curve will be determined in the results post.

Entry format

For this contest, I expect to see entries made in the following format:

Non-fiction books
Quantity: XXX Selling Price: XXX
Fiction books
Quantity: XXX Selling Price: XXX
Children’s books
Quantity: XXX Selling Price: XXX

Non-fiction books
Quantity: 20 (2 batches) Selling Price: $12.20
Fiction books
Quantity: 20 (1 batch) Selling Price: $15.50
Children’s books
Quantity: 120 (4 batches) Selling Price: $7

The closing date and time for this contest is 6PM coordinated universal time (UTC) 26/09/2021. Responses after this time will not be accepted. The answers will be provided in the results post along with the video containing the generation of demand and profits using the model.

I hope everyone has fun and enjoys the business version of the contest. If you have any questions, feel free to ask in the comments section.

More posts


If you want to read any of my other posts, you can click on the links below. These links will lead you to posts containing my collection of works. These 'Collection of Works' posts have been updated to contain links to the Hive versions of my posts.





My CBA Udemy Course


The course contains over 10 hours of video, over 60 downloadable resources, over 40 multiple-choice questions, 2 sample case studies, 1 practice CBA, life time access and a certificate on completion. The course is priced at the Tier 1 price of £20. I believe it is frequently available at half-price.

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Welcome back!

Non-fiction books
Quantity: 10 Selling Price: $12
Fiction books
Quantity: 60 Selling Price: $10.75
Children’s books
Quantity: 60 Selling Price: $6.75

Posted Using LeoFinance Beta

Been a while you've hosted the Buying and Selling Game, it's been more of actifit for you lately. good to see it back.

@tipu curate

Thanks, it's good to be back.

Only 30 Hive? Make it 33 Hive and we have a deal. Oh wait, this is not a negotiating game.

Let’s play!

Sure, go for it.

The rewards earned on this comment will go directly to the person sharing the post on Twitter as long as they are registered with @poshtoken. Sign up at

Thank you, @spectrumecons, for your interest in my Lebanon post :) As a global citizen (part Egyptian, Lebanese, living in America and married to a Colombian girl) I'm fascinated by the idiosyncrasies of different cultures as well as what unites us.

I do hope my words will continue to keep you good company 😇