CAIE A-Level Economics 2.3.3 PES Coefficient

CAIE A-Level Economics 2.3.3 PES Coefficient
Cambridge International AS & A Level Economics 9708 syllabus for exams in 2026, 2027 and 20282026–2028

Practise interpreting PES coefficients and supply-curve geometry, including unitary, perfectly elastic and perfectly inelastic supply at different points on a curve.

How this is tested

  • classify PES above one as elastic, below one as inelastic and equal to one as unitary
  • recognise vertical supply as perfectly inelastic and horizontal supply as perfectly elastic
  • interpret how PES can vary along a straight supply curve after a price or tax change

Question 6

[Maximum number: 1]

A theatre has a fixed number of tickets to sell for each performance.
What is the price elasticity of supply?

A

perfectly elastic

B

perfectly inelastic

C

unit elastic and negative

D

unit elastic and positive