SOLUTION: When Emily went to the emergency room, the doctors gave her a dose of blood coagulant, which is just a type of drug that helps blood clot. If the doctors originally gave Emily 4 mi

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Question 1140026: When Emily went to the emergency room, the doctors gave her a dose of blood coagulant, which is just a type of drug that helps blood clot. If the doctors originally gave Emily 4 milligrams of the drug and expect the amount in her bloodstream to decrease by 45% each hour, how many milligrams of the drug will be in her bloodstream after 6 hours? Round your answer to two decimal places.
I tried starting it but became lost in the wording. Someone please help
Found 2 solutions by josgarithmetic, Theo:
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
This may be less efficient than you want:
TIME, hours         AMOUNT, mg

0                     4

1                    0.55*4=2.2

2                   0.55*2.2=1.21

3                  0.55*1.21=0.6655

4                  0.55*0.6655=0.366025

5                  0.55*0.366025=0.20131375

6                  0.55*0.20131375=0.1107226

You should be able to use the pattern to form an equation.

Your final number should be 0.1 milligrams.

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
she originally got 4 milligrams.
the amount in her bloodstream decreases by 45% every hour.
after 6 hours, how much will be left in her bloodstream?

if the amount of the drug decreases by 45% every hour, then the remaining amount of the drug every hour would be 100% - 45% = 55% of what it was the previous hour.

55% is equal to .55.

you need to multiply the amount of drug in her bloodstream by .55 every hour.

in 6 hours, you would be multiplying 4 by .55 ^ 6 to get .11007225625 milligrams left in her bloodstream.

that's your solution.

the following excel spreadsheet shows the individual calculations for each hour.

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