Solving John's Pencil And Pen Purchase For A Conference A Mathematical Problem

by ADMIN 79 views

Introduction

In this article, we will delve into a mathematical scenario involving John, who is preparing for a conference. John needs to purchase writing instruments for the attendees, specifically pencils and pens. He buys boxes of pencils, each containing a fixed number of pencils, and packets of pens, each containing a fixed number of pens. John's goal is to provide each person at the conference with one pencil and one pen. At the end of the conference, John finds that he has no pencils left but has some pens remaining. This situation presents an intriguing problem that we can solve using mathematical principles. The core concept we will explore revolves around understanding how the number of items in each box and packet, the number of attendees, and the remaining items are related. By analyzing these relationships, we can deduce important information about the conference, such as the number of attendees and the initial quantities of pencils and pens John purchased. This problem is a practical application of basic arithmetic and algebra, demonstrating how these mathematical tools can be used to solve real-world scenarios. Understanding how to approach such problems is crucial for developing problem-solving skills and enhancing our ability to apply mathematical concepts in various contexts. We will break down the problem step by step, identifying the key information and using it to form equations that will lead us to the solution. The focus will be on clarity and logical reasoning, making the solution accessible and understandable. This exercise not only reinforces mathematical concepts but also highlights the importance of careful planning and resource management in event organization.

Problem Statement

John's procurement problem involves purchasing boxes of pencils and packets of pens for a conference. Each box contains 40 pencils, and each packet contains 15 pens. John distributes one pencil and one pen to each attendee. After the conference, John has no pencils remaining but still has some pens left over. The question is to determine the number of pens John has left. To solve this, we need to find the lowest common multiple (LCM) of the number of pencils per box and the number of pens per packet, which are 40 and 15, respectively. The LCM will give us the smallest number of attendees for which John's pencil distribution works out perfectly, meaning he has no pencils left. We will use this number to figure out how many boxes of pencils John bought initially. Then, we will look at the pens, using the same number of attendees to calculate how many pens were distributed. Comparing the number of pens John initially had with the number distributed will tell us how many pens remain. This problem illustrates the importance of understanding common multiples and how they apply to real-world distribution problems. It's a great example of using math to manage resources effectively. By breaking down the problem into smaller parts, we can clearly see the relationships between the quantities and use those relationships to find our answer. The problem also emphasizes the need for careful planning to ensure resources are used efficiently, a valuable skill in many aspects of life and work.

Setting up the Equations

To effectively solve John's procurement puzzle, let's define some variables to represent the unknowns in the problem. Let 'x' be the number of boxes of pencils John bought, and let 'y' be the number of packets of pens John bought. We will also let 'n' represent the number of people attending the conference. Based on the information given, we can create two equations. The first equation represents the pencils: Since each box contains 40 pencils and John has no pencils left after giving one to each person, the total number of pencils must equal the number of attendees. This can be written as: 40x = n. The second equation represents the pens: Each packet contains 15 pens, and John gives one pen to each person. Since John has some pens left, we know that the total number of pens he bought is more than the number of attendees. We can represent this as: 15y > n. These two equations form the foundation for our solution. The first equation tells us that the number of attendees must be a multiple of 40, since the total pencils are divided evenly among the attendees. The second equation gives us an inequality, indicating that the total number of pens bought exceeds the number of attendees. To solve the problem, we need to find the values of x, y, and n that satisfy both equations. This involves using our understanding of multiples and inequalities to narrow down the possibilities. The setup of these equations is a critical step in mathematical problem-solving, as it translates the word problem into a mathematical form that can be analyzed and solved. Accurate representation of the problem in equation form is crucial for arriving at the correct solution.

Finding the Number of Attendees

To determine the number of attendees at the conference, we need to analyze the equations we've set up. We know that 40x = n, which means the number of attendees, 'n', must be a multiple of 40. This is because John distributed all the pencils, and there were 40 pencils in each box. Now, we also know that John gave each attendee one pen, and he had some pens left over. This means that the total number of pens he bought (15y) is greater than the number of attendees ('n'). To find a suitable value for 'n', we need to consider the multiples of 40 and see how they relate to multiples of 15. The key is to find a multiple of 40 that is also less than some multiple of 15. This is where the concept of the least common multiple (LCM) comes in handy. The LCM of two numbers is the smallest number that is a multiple of both. However, in this case, we are not looking for the LCM of 40 and 15 directly, but rather a multiple of 40 that fits our inequality condition (15y > n). We can start by listing multiples of 40: 40, 80, 120, 160, 200, and so on. Then, we can check if these multiples can be a possible number of attendees by seeing if there's a corresponding number of pen packets that would leave some pens leftover. For example, if we consider 40 attendees, John would need 1 box of pencils. To have more pens than attendees, he would need at least 3 packets of pens (15 * 3 = 45 pens), which is more than 40. This is a valid possibility. We continue checking multiples of 40 until we find one that gives us a reasonable solution. This process of checking multiples helps us narrow down the possibilities and find the correct number of attendees, which is a crucial step in solving the problem.

Calculating the Pens Remaining

Once we determine the number of attendees, we can proceed to calculate the number of pens remaining after the conference. Let's assume, for the sake of illustration, that we've found the number of attendees to be 120. This means John bought 120 pencils, which translates to 3 boxes of pencils (since 120 / 40 = 3). Now, let's figure out how many packets of pens John bought. We know that 15y > 120, where 'y' is the number of packets of pens. To find the smallest whole number value for 'y' that satisfies this inequality, we can divide 120 by 15, which gives us 8. Since 15 * 8 = 120, we need 'y' to be greater than 8. Let's try y = 9. This means John bought 9 packets of pens, totaling 15 * 9 = 135 pens. To find the number of pens remaining, we subtract the number of attendees (120) from the total number of pens (135): 135 - 120 = 15 pens. So, in this scenario, John would have 15 pens left. This calculation demonstrates how we use the number of attendees and the number of pens per packet to find the total pens and then subtract the distributed pens to find the remainder. The key is to use the information we have to set up the calculation correctly. The remaining pens are simply the difference between the total pens and the pens given out. This step is crucial in answering the problem's core question: how many pens does John have left? By carefully working through the math, we arrive at the solution, showcasing the practical application of subtraction in real-world scenarios.

General Solution and Conclusion

In summary, John's resource management problem involves finding the number of pens remaining after a conference, given the number of pencils and pens he bought and the number of attendees. We established that the number of attendees (n) is a multiple of 40 (40x = n) and that the total number of pens (15y) is greater than the number of attendees (15y > n). By considering multiples of 40 and their relationship to multiples of 15, we can determine a possible value for 'n' and subsequently calculate the number of pens remaining. The general approach involves finding a multiple of 40 that, when used as the number of attendees, results in a whole number of boxes of pencils being used. Then, we find a number of packets of pens such that the total pens are greater than the number of attendees. The difference between the total pens and the attendees gives us the number of pens remaining. This type of problem highlights the practical application of basic mathematical concepts such as multiples, inequalities, and subtraction. It demonstrates how we can use math to solve real-world scenarios involving resource distribution and management. The key to solving such problems is to break them down into smaller, manageable steps, define variables to represent unknowns, and set up equations that accurately reflect the given information. By following this approach, we can logically deduce the solution and gain a deeper understanding of the mathematical principles involved. This problem also underscores the importance of careful planning and resource allocation in events and conferences, ensuring that materials are used efficiently and effectively.