Business Statistics: For Contemporary Decision Making, 7th Edition

SUPPLEMENT 1

SUMMATION NOTATION

In Chapter 3, the symbol Σ (the Greek letter sigma) was introduced. In mathematics, this symbol means to sum a set of values as described by the notation following it. The value given below Σ is the beginning value and the value given above Σ is the final value of the sum. Generally,

For example, if x₁ = 3, x² = 5, x³ = 7, and x⁴ = 12,

The second summation rule is:

For example, if c = 8, x¹ = 3, x² = 5, x³ = 7, and x⁴ = 12,

and

The third summation rule is

For example, if x¹ = 2, x² = 4, x³ = 5, x^y1 = 1, x^y = 3, and x^y3 = 6,

and

The fourth summation rule is:

For example, if c = 12 and n = 5,

but 60 = 5(12), so