Question

Suppose the market demand curve for a good is Qd=1000-10p and the market supply curve is given by Qs=100+20p required; calculate the equilibrium price and the equilibrium quantity

Answer 1

At equilibrium price, both $Qd = Qs$,

Therefore, $Qd=1000-10p=Qs=100+20p \\ 1000-10p =100 + 20p\\ 1000-100 = 20p+10p\\ 900=30p\\ p=30$

Equilibrium price = 30

$Qd=1000-10p\\ Qd = 1000-10(30)\\ Qd = 700$

Equilibrium quantity = 700