→∴ needed! any answers that don't will be removed. ∴←an adult can take 400 mg of ibuprofen. each hour, the amount of ibuprofen decreases by 25%. how much ibuprofen is left in the system after 6 hours? show your work and i will give you brainliest : )

Let be the number of hours that have passed since taking the ibuprofen, and let be the amount of ibu left after hours. At the start, all the ibu remains intact, so that mg.

After the first hour, 75% remains, so that mg.

After the second hours, we're left with mg.

And so on. You'll notice that the amount of ibu remaining at hour forms a geometric sequence with the general form

We can solve explicitly for :

and so on, with the general pattern of

After 6 hours, we're left with

mg

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft

what