Trivia Cafe
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Can you find a pair of numbers whose sum is 100 and whose product is 2356?

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mathematics

The pair of numbers that fits both criteria is 38 and 62. If you add 38 and 62 together, their sum is exactly 100. When you multiply them, 38 times 62 yields 2356. This demonstrates how these two specific integers fulfill the conditions of the puzzle.

This type of problem, where you're given the sum and product of two unknown numbers, is a classic mathematical challenge. It's directly linked to the roots of a quadratic equation. In algebra, if you have a quadratic equation in the form x^2 - (sum of roots)x + (product of roots) = 0, the solutions for x will be the two numbers you're looking for. For this particular puzzle, the corresponding equation would be x^2 - 100x + 2356 = 0. Solving this equation, whether by factoring, completing the square, or using the quadratic formula, would reveal 38 and 62 as its two roots.

An alternative, often more intuitive, approach is to recognize that two numbers with a fixed sum will be closest to each other when they are equal. Since the sum is 100, the average value is 50. We can then represent the numbers as (50 - x) and (50 + x). Their product would be (50 - x)(50 + x), which simplifies to 50^2 - x^2, or 2500 - x^2. Setting this equal to the given product, 2356, we get 2500 - x^2 = 2356. Solving for x, we find x^2 = 144, meaning x = 12. Substituting x back into our expressions gives us 50 - 12 = 38 and 50 + 12 = 62, confirming the solution.