00:01
So you run a small business and would like to predict what will happen to the quantity demanded for your product if you raise the price.
00:08
So you want to increase price and then you want to know what's going to happen to the quantity demanded when you increase the price.
00:17
So while you do not know the exact demand call for your product, you do know that in the first year, you charge $45, i'm calling it.
00:33
You charge $45 and you sold the units you sold or rather quantity you sold was 1 ,200 units and that in the second year you'll charge $30 rather and you sold 1 ,800 units.
01:03
Now, the first question is if you plan to raise your price by 10%, what? would be a reasonable estimate of what will happen to the quantity demanded in percentage terms so giving the question um we're going to substitute the values in the equation so as price elasticity of demand so price elasticity of demand um we're going to have forty five dollars divided by one thousand two hundred multiplied by six hundred divided by minus 15 and then that's um i'm sorry i didn't explain where the 600 came from um so first of all we calculate the elasticity of demand by using the formula which is the price over i'm sorry let me just start over so the formula is p over q multiplied by the change in quantity over the change in price so the initial price as you can see is 45 the quantity the quantity is 1 ,200.
02:33
So therefore, the change in the quantity would be 1 ,200, 1 ,800 minus 1 ,200.
02:40
So that's going to be 600, right? and then the change in the price would be 45 minus 30, rather 30 minus 45.
02:51
So that's minus $15 because it's the new one minus the old one, right? so the second year minus the first year.
02:58
So now knowing that, knowing those figures you can find the price elasticity of demand so that will be equals to the price is 45 the quantity is 1 ,200 and then the change is 600 as you can see divided by minus 15 so now we get that so this is going to give you minus 1 .5 and that's the price elasticity of demand so the negative sign denotes that it has the inverse relation between the price and quantity demanded so we can can say that it has an inverse relation between price and quantity demanded.
03:46
So now, as per the first question, if the firm owner plans to increase the price by 10%, then the quantity, the change in quantity demanded will be price elasticity of demand is equal to the percent change in quantity demanded divided by the percent change in price.
04:08
So here we have the price elasticity of demand as minus 1 .5.
04:13
So minus 1 .5 will be the change in quantity demanded, the percentage change in quantity demanded, divided by 10%, because the percentage change in price, as part of the question, is 10%.
04:26
So this is going to give you minus 15 % when you multiply it by 10 is equal to the percentage change in quantity demanded...