The dating math problem
One of the most well-known applications of half-life is carbon-14 dating.The half-life of carbon-14 is approximately 5,730 years, and it can be reliably used to measure dates up to around 50,000 years ago.Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value.The term is most commonly used in relation to atoms undergoing radioactive decay, but can be used to describe other types of decay, whether exponential or not.
Her mother, Jenn Morrison Douglas, posted the maths question on Facebook with the hashtag #girlcodetrumpscommoncore.
Also, the problem serves as a nice introduction to the general area of statistical decision making.
As always, we must start with a clear statement of the problem.
Step 1: Take the words from the question, and write it down as an equation - 6/n x 5/(n-1) = 1/3 Step 2: Multiply the 6 by the 5 and the n by the n-1.
That gives you: 30/(n^2 - n) = 1/3 Step 3: Multiply the top-left by bottom-right and top-right by bottom-left Step 4: Subtract 90 from both sides, leading to your answer n^2 - n - 90 = 0 You should create a table of four columns with the months at the top and the dates Cheryl gives after. For Albert to have known the answer, he would have to have May and June as that is when 19 or 18 occur." The number 14 is the only one in both months but Bernard is now sure of the birth date.
These patterns twist and turn and warp and evolve just as love does, and are all patterns which mathematics is uniquely placed to describe. It is the foundation stone upon which every major scientific and technological achievement of the modern era has been built. In the first chapter, Fry explores the mathematical odds of finding your ideal mate — with far more heartening results than more jaundiced estimations have yielded.