Consider the demand curve D (p) = 10 – 3p. What is the elasticity at price 5/3?
D(p) = 10 – 3p
This implies Δq/Δp = -3
At p = 5/3
q will be = 10 – (3x5/3) = 5
Ed = Δq/Δp X p/q
= -1