# Homework Help: Price elasticity of demand

1. Nov 18, 2013

### EdmureTully

1. The problem statement, all variables and given/known data

Given a price elasticity of 1.6 and an initial sales number of 10000 what would be the sales number if price went from 4.99 to 10.00?

2. Relevant equations

Price Elasticity of Demand = % Change in Quantity Demanded / % Change in Price

3. The attempt at a solution

1.6*200 *100 -10000

it gives me 220000, but that can't be right

2. Nov 19, 2013

### Ray Vickson

What is the formula for Quantity as a function of price? It is the solution of a differential equation; first write out the equation, then solve it. Once you have done that it is a simple matter of substitution.

3. Nov 20, 2013

### EdmureTully

I don't have that formula. It's not even a homework problem. I just want to know how to determine the new quantity.

4. Nov 21, 2013

### Ray Vickson

You may not "have that formula", but I have told you what you need to do to get it. The rest is up to you.