After 24 hours, 30% of a 25 milligram dose of a new antibiotic remains in the body. Which of the following functions, M, models the amount of the antibiotic (in milligrams) that remains in the body after h hours?Choose 1 answer:(A) M(h)=30×(0.3)(24h)(B)M(h)=25×(0.3)(24h)(C) M(h)=25×(0.3)h(D) M(h)=25×(0.7)(24h)
Q. After 24 hours, 30% of a 25 milligram dose of a new antibiotic remains in the body. Which of the following functions, M, models the amount of the antibiotic (in milligrams) that remains in the body after h hours?Choose 1 answer:(A) M(h)=30×(0.3)(24h)(B)M(h)=25×(0.3)(24h)(C) M(h)=25×(0.3)h(D) M(h)=25×(0.7)(24h)
Given Information: We are given that 30% of the antibiotic remains after 24 hours. This means that after 24 hours, the amount of antibiotic left is 30% of the initial dose. We need to find a function that models this decay over time.
Initial Dose: The initial dose of the antibiotic is 25 milligrams. We need to express the remaining amount as a function of time, where time is measured in hours (h).
Percentage Calculation: Since 30% remains after 24 hours, we can express this as a percentage of the initial dose: 30% of 25 milligrams. To convert the percentage to a decimal, we divide by 100: 30%=0.3.
Exponential Decay Function: The decay of the antibiotic in the body is exponential, and it can be modeled by an exponential decay function. The general form of an exponential decay function is M(h)=initial_amount×(decay_rate)(time/decay_time).
Finding Decay Rate: We need to find the decay rate. After 24 hours, 30% of the antibiotic remains, so the decay rate must be such that when h=24, the function gives us 30% of the initial dose. This means that the decay rate raised to the power of (24/24) should equal 0.3.
Decay Rate Calculation: The decay rate should be such that (decay_rate)1=0.3. Since raising any number to the power of 1 gives the number itself, the decay rate is 0.3.
Writing the Function: Now we can write the function using the initial amount of 25 milligrams and the decay rate of 0.3. The time h will be divided by the period of decay, which is 24 hours, to model the decay over time. This gives us the function M(h)=25×(0.3)(h/24).
Matching the Function: Looking at the options provided, option (B) matches the function we derived: M(h)=25×(0.3)24h. This function correctly models the amount of the antibiotic that remains in the body after h hours, given that 30% remains after 24 hours.
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