Skip to main content
Ch. 3 - Derivatives
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Not the one you use?Change textbook
Chapter 3, Problem 33a

Demand and elasticity Based on sales data over the past year, the owner of a DVD store devises the demand function D(p)=402pD(p) = 40-2p , where D(p) is the number of DVDs that can be sold in one day at a price of p dollars.
a. According to the model, how many DVDs can be sold in a day at a price of \$10?

Verified step by step guidance
1
Identify the demand function given in the problem: \( D(p) = 40 - 2p \).
Substitute the price \( p = 10 \) into the demand function.
Calculate \( D(10) = 40 - 2(10) \).
Simplify the expression to find the number of DVDs sold.
Interpret the result to understand how many DVDs can be sold at the price of \$10.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Demand Function

A demand function expresses the relationship between the price of a good and the quantity demanded by consumers. In this case, the function D(p) = 40 - 2p indicates that as the price (p) increases, the quantity of DVDs sold (D) decreases. This linear relationship helps predict sales at different price points.
Recommended video:
06:21
Properties of Functions

Elasticity of Demand

Elasticity of demand measures how sensitive the quantity demanded is to a change in price. It is calculated as the percentage change in quantity demanded divided by the percentage change in price. Understanding elasticity helps businesses make informed pricing decisions to maximize revenue.
Recommended video:
04:18
Maximizing Profit & Revenue

Substitution and Revenue Maximization

Substitution refers to how consumers may switch to alternative products as prices change. For the DVD store, if prices rise significantly, customers might choose digital streaming instead. Revenue maximization occurs when the price is set at a level where the product's demand is balanced with consumer willingness to pay, ensuring optimal sales and profit.
Recommended video:
04:18
Maximizing Profit & Revenue