00:01
So here we're talking about elasticity, and we're not just talking about any elasticity.
00:05
We're talking about the elasticity of demand.
00:08
What is the elasticity of demand? it's a ratio that measures how the quantity demand it changes, that's a d, relative to the change in the price, right? so it's saying if the price changes by x, compare that the change in quantity, and that ratio gives me the elasticity.
00:26
So we know this elasticity is minus 1 .5.
00:30
You that the change in quantity is going to be 1 .5 times as large as the change in price, and it will have the opposite sign.
00:39
So we know that the quantity demanded starts off at 40 ,000.
00:44
So for a, we have the percentage change in price is equal to 10%.
00:52
So we can rearrange.
00:55
And if we rearrange, range, we get the percentage change in the quantity supplied is equal to the elasticity.
01:02
We usually call this epsilon, squiggly, e, times the percentage change in the price, minus 1 .5 times 10 % is equal to minus 15%...