Three marbles are assigned to three people and a box is addressed to each of them. the marbles are inserted into the boxes at random so that each box contains one marble. find the probability that at least 1 marble is sent in the proper box.
a.) 2/3
b.) 1/3
c.) 1/9
d.) 1/4

step-by-step explanation:

for exempl this   system of equations   y = x - 3

                                                                y = 2x - 5

look   the line : y = x -3     ( red)

                            the line : y = 2x -5 ( bleus)

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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