Fernando's Money Puzzle: How Much Did He Start With?

by Omar Yusuf 53 views

Hey guys! Let's dive into a fun math problem today, a real-life scenario where we figure out how much money someone had initially. This is the kind of problem that can seem tricky at first, but we'll break it down step by step. Our friend Fernando is on a shopping spree, and we need to trace back his steps to find out his original stash of cash. Let's get started!

The Shopping Spree Breakdown

Fernando's financial journey begins with an unknown amount of money. He spends a portion of it on various items, and we need to backtrack to find the starting amount.

First, Fernando spends 2/15 of his money on a stylish tie. This means that out of every 15 parts of his money, 2 parts went towards the tie. Next up, he spends 3/8 of the remaining money on a smart shirt. This is crucial – it's 3/8 of what's left after buying the tie, not 3/8 of the original amount. Then, he decides to grab a fancy wallet, spending 5/13 of what's still left. Finally, with the last 40 soles, Fernando treats himself to a bottle of cologne. The challenge is to figure out how much money Fernando had at the very beginning of his shopping trip. We're essentially reverse-engineering his spending habits to uncover the initial amount. This problem showcases how fractions and working backwards can help us solve everyday financial puzzles. So, let’s put on our thinking caps and unravel this mystery!

Unraveling the Mystery: Working Backwards

To solve this problem effectively, we'll use a step-by-step approach, working backwards from the final amount. This method allows us to undo each transaction and gradually reveal Fernando's initial money.

Starting with the cologne: Fernando had 40 soles left after buying the wallet. This 40 soles represents the fraction of money he had remaining after purchasing the wallet. To figure out the amount before the wallet purchase, we need to determine what fraction of his money was left at this stage. He spent 5/13 on the wallet, so he had 1 - 5/13 = 8/13 of his money remaining. This means that 40 soles is equal to 8/13 of the money he had before buying the wallet. To find the whole amount (13/13), we can set up a simple equation: (8/13) * x = 40, where x is the amount before buying the wallet. Solving for x, we get x = 40 * (13/8) = 65 soles. So, Fernando had 65 soles before buying the wallet. This is a crucial step, as it lays the foundation for our backward journey. We are now one step closer to discovering the initial sum. Remember, each step involves reversing the fractional spending, and this method of working backwards is a powerful tool for solving similar problems.

The Shirt and Tie Expenses: Reconstructing Fernando's Budget

Having figured out Fernando's money before the wallet purchase, our next task is to account for the shirt and tie expenses. This involves reversing the fractions spent on these items to reveal the amounts before each purchase.

Before the wallet, Fernando had 65 soles. Now, let's rewind to before he bought the shirt. He spent 3/8 of his money on the shirt, meaning the 65 soles represents 1 - 3/8 = 5/8 of the money he had at that point. To find the amount before the shirt, we set up another equation: (5/8) * y = 65, where y is the amount before the shirt purchase. Solving for y, we get y = 65 * (8/5) = 104 soles. So, Fernando had 104 soles before buying the shirt. We're making progress! Now, we need to go back one step further, to before the tie purchase. Fernando spent 2/15 of his original money on the tie. This means the 104 soles represents 1 - 2/15 = 13/15 of his original amount. To find the original amount, we set up our final equation: (13/15) * z = 104, where z is the original amount. Solving for z, we get z = 104 * (15/13) = 120 soles. Therefore, Fernando initially had 120 soles. This meticulous step-by-step approach, reversing each expense, has led us to the final answer. Understanding how to handle fractions and work backwards is key to solving these kinds of financial puzzles.

Final Answer: Fernando's Initial Fortune

After carefully tracing Fernando's spending spree, we've arrived at the answer: Fernando initially had 120 soles. This journey through his expenses, reversing each transaction, highlights the power of mathematical problem-solving in real-life scenarios.

To recap, we started with the final amount (40 soles for cologne) and worked backwards, accounting for the wallet (5/13), the shirt (3/8), and finally the tie (2/15). Each step involved understanding the remaining fraction of money and calculating the amount before each purchase. This method of reversing the transactions is a valuable skill for solving problems where you need to find the initial amount after a series of changes. It's like being a financial detective, piecing together the clues to solve the mystery! Problems like these not only enhance our mathematical skills but also provide insights into managing personal finances. By understanding how fractions and percentages work in spending scenarios, we can make informed decisions and avoid financial pitfalls. So, the next time you encounter a similar puzzle, remember the step-by-step backward approach, and you'll be well-equipped to crack the code!

Key Takeaways and Learning Points

This problem demonstrates several key mathematical concepts and problem-solving strategies. Understanding these takeaways can help you tackle similar challenges in the future.

Fractions are your friends: A core element of this problem is understanding and manipulating fractions. We dealt with fractions representing portions of money spent, and we had to calculate the remaining fractions after each purchase. Being comfortable with fraction operations (addition, subtraction, multiplication, and division) is crucial for solving these kinds of problems. Remember, the denominator represents the total parts, and the numerator represents the parts being considered. Visualizing fractions can also be helpful. For example, thinking of 2/15 as 2 parts out of 15 can make the concept more concrete.

Working backwards is powerful: The most effective strategy for this problem was working backwards. Instead of trying to calculate Fernando's spending in a forward manner, we started with the final amount and reversed each transaction. This approach simplifies the problem by breaking it down into smaller, manageable steps. It's a technique that can be applied to a wide range of problems, not just financial ones. Think of it as retracing your steps to find where you started.

Step-by-step approach is crucial: Breaking the problem down into smaller steps made it less overwhelming. We tackled each expense individually, which allowed us to focus on one calculation at a time. This systematic approach is essential for complex problems. It ensures you don't miss any crucial details and helps you stay organized.

Real-life applications of math: This problem highlights the practical applications of math in everyday life. Understanding how to calculate spending, manage budgets, and solve financial puzzles is a valuable skill. Math isn't just abstract equations; it's a tool that can help us navigate the real world more effectively.

Double-checking your work is essential: After arriving at the final answer, it's always a good idea to double-check your work. You can do this by retracing your steps or using a different method to solve the problem. In this case, you could try calculating Fernando's spending in a forward manner to see if it matches the given information. This reinforces your understanding and helps you catch any errors. By mastering these concepts and strategies, you'll be well-prepared to solve a variety of math problems and make informed decisions in real-life situations.