JAMB Economics 2017 Paper

Arithmetic mean, x̄= ∑fx
n
where:
x̄= Arithmetic mean
∑ = sum of
X = series of figures in a given data
f = nunmber of times a particular number occurs (frequency)
n = number of figures or element
From the question:
Since, x̄= ∑fx
N
Then, x̄= ∑fx
N
=

340

20

= 17