Paper 1 Formulas

Question 1

Market share

Answer 1

Total sales of one firm
——————————— x 100
Total market sales

Question 2

Market size

Answer 2

?

Question 3

PED

Answer 3

% change in QD
————————
% change in price

> 1 = elastic
<1 = inelastic

Question 4

YED

Answer 4

% a change in QD
————————
% change in income

<1 = normal good
>1 = luxury goods
-number = inferior good