If an adult takes 400 milligrams of ibuprofen and the amount of ibuprofen decreases by 29 percent every hour how much ibuprofen would be left after 6 hours?

To calculate the remaining ibuprofen after 6 hours, you can use the formula for exponential decay: ( A = P(1 - r)^t ), where ( A ) is the amount remaining, ( P ) is the initial amount (400 mg), ( r ) is the decay rate (0.29), and ( t ) is the time in hours (6).

Substituting the values, you get: [ A = 400(1 - 0.29)^6 ] [ A = 400(0.71)^6 \approx 400 \times 0.117 \approx 46.9 \text{ mg} ]

After 6 hours, approximately 46.9 milligrams of ibuprofen would be left.