Answer AND Step-by-step explanation:
Everything is in the picture.
<em><u>#teamtrees #PAW (Plant And Water)</u></em>
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<u>The equation is:</u>
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<span>As the age of the U-235 sample is 2.631 billion years, and the half-life of U-235 is 713 million years, the sample has undergone 2.361 X 1,000,000,000 / 713 X 1,000,000 = 3.69 half lives. In each half-life the sample reduces to half its original weight according to the radioactive Half-Life Formula:
ln (Nt /N0) = -kt, where N0 = mass of the original weight of radioactive material, Nt = mass of radioactive material at time t, k = decay constant and t = time interval . We have to put Nt/N0 = 1/2 for time interval = half-life.</span>

For unorganized data, median is the middle value when the numbers are arranged in ascending order.
Let's proceed ~
In ascending order :
12, 13, 23, 26, 26, 35, 38, 44, 47
So, for given data... median is 26