/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 11 A 50 mg dose of quinine is given... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A 50 mg dose of quinine is given to a patient to prevent malaria. Quinine leaves the body at a rate of \(6 \%\) per hour. (a) Find a formula for the amount, \(A\) (in \(\mathrm{mg}\) ), of quinine in the body \(t\) hours after the dose is given. (b) How much quinine is in the body after 24 hours? (c) Graph \(A\) as a function of \(t\) (d) Use the graph to estimate when 5 mg of quinine remains.

Short Answer

Expert verified
(a) Formula: \( A(t) = 50 \times 0.94^t \) (b) 14.31 mg (c) Use a graphing tool to plot (d) About 50 hours.

Step by step solution

01

Define the Problem

We need to determine how quinine exits the body over time and develop a mathematical model for this process.
02

Establish the Rate Function

Quinine leaves the body at a rate of 6% per hour. This can be represented by the exponential decay formula, where the rate of decay is 6% per hour.
03

Derive the Exponential Decay Formula

The general formula for exponential decay is given by \( A(t) = A_0 \times (1 - r)^t \), where \( A_0 \) is the initial amount, \( r \) is the decay rate, and \( t \) is time in hours. Here, \( A_0 = 50 \) mg and \( r = 0.06 \). Thus, the formula becomes \( A(t) = 50 \times 0.94^t \).
04

Calculate Amount After 24 Hours

To find the amount of quinine after 24 hours, substitute \( t = 24 \) into the formula: \( A(24) = 50 \times 0.94^{24} \). Calculate to find the result.
05

Graph the Function

Create a plot of the function \( A(t) = 50 \times 0.94^t \) to visualize how the amount of quinine decreases over time. Use a graphing tool to draw the graph with \( t \) on the x-axis and \( A(t) \) on the y-axis.
06

Estimate Time for 5 mg

Using the graph, find the point where the amount of quinine is approximately 5 mg. This corresponds to when \( A(t) = 5 \).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Calculating Medicinal Dosage
Medicinal dosage calculations, especially when dealing with drugs like quinine, are crucial for ensuring safe and effective treatment. In our example, we start with a 50 mg dose of quinine, given to battle malaria. The key challenge is to figure out how much of this drug remains in the body over time. This is due to the body's natural process of eliminating substances, which for quinine happens at a rate of 6% per hour. To determine the remaining dosage, we use the formula for exponential decay: \[ A(t) = A_0 \times (1 - r)^t \] Here:
  • \(A_0\) represents the initial dose, which is 50 mg.
  • \(r\) is the decay rate, 6% (or 0.06 in decimal).
  • \(t\) denotes time in hours.
Plugging in our values gives us \( A(t) = 50 \times 0.94^t \). This formula allows us to calculate how much quinine is left in the body after any number of hours.
Graphing Exponential Functions
Visualizing how quinine levels decrease can be very insightful. We can achieve this through graphing. By plotting the function \( A(t) = 50 \times 0.94^t \), we create a visual representation of the drug's presence over time. In this graph, the horizontal axis (x-axis) marks time in hours, while the vertical axis (y-axis) shows the amount of quinine in mg. As time progresses, you should notice a downward slope, characteristic of exponential decay, reflecting how the drug diminishes.Graphing helps in:
  • Checking your calculations visually.
  • Estimating key points, such as when only a specific amount (e.g., 5 mg) remains.
  • Understanding the practical implications of dosage schedules.
To determine when exactly 5 mg remains, one can look at where the graph crosses the y-value of 5 mg.
Mathematical Modeling in Medicine
Mathematical modeling plays a vital role in healthcare, particularly in drug dosing. By employing models like exponential decay, healthcare professionals can predict how drugs metabolize within the body. This aids in creating effective dosing schedules, minimizing side effects, and ensuring the medication remains at therapeutic levels. In medical modeling, understanding how decay functions operate is essential because:
  • They provide precise quantifiable data over time.
  • These models simplify complex biological processes into understandable patterns.
  • Accurate predictions help in designing treatment plans for different patients based on their metabolic rates.
For quinine, modeling helps ensure that the levels stay effective to combat malaria without the need for frequent dosing, ultimately improving treatment adherence and outcomes.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Most breeding birds in the northeast US migrate elsewhere during the winter. The number of bird species in an Ohio forest preserve oscillates between a high of 28 in June and a low of 10 in December. \(^{97}\) (a) Graph the number of bird species in this preserve as a function of \(t,\) the number of months since June. Include at least three years on your graph. (b) What are the amplitude and period of this function? (c) Find a formula for the number of bird species, \(B\), as a function of the number of months, \(t\) since June.

You are buying a car that comes with a one-year warranty and are considering whether to purchase an extended warranty for 375 . The extended warranty covers the two years immediately after the one-year warranty expires. You estimate that the yearly expenses that would have been covered by the extended warranty are 150 at the end of the first year of the extension and 250 at the end of the second year of the extension. The interest rate is \(5 \%\) per year, compounded annually. Should you buy the extended warranty? Explain.

Find the present value of a \(\$ 20,000\) payment to be made in 10 years. Assume an interest rate of \(3.2 \%\) per year compounded continuously.

During a recession a firm's revenue declines continuously so that the revenue, \(R\) (measured in millions of dollars), in \(t\) years' time is given by \(R=5 e^{-0.15 t}\) (a) Calculate the current revenue and the revenue in two years' time. (b) After how many years will the revenue decline to \(\$ 2.7\) million?

The population, \(P\), in millions, of Nicaragua was 5.4 million in 2004 and growing at an annual rate of \(3.4 \% .\) Let \(t\) be time in years since 2004 (a) Express \(P\) as a function in the form \(P=P_{0} a^{t}\) (b) Express \(P\) as an exponential function using base \(e\) (c) Compare the annual and continuous growth rates.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.