Question

Calculate each value requested for the following set of scores.a. ΣΧ=b. ΣΧ2=c. (ΣΧ)2=d. SS=Scores: 2, 3, 0,5Round to the hundredths place.

Answer 1

a.

$\Sigma x=2+3+0+5=5+5=10$

b.

$\Sigma x^2=2^2+3^2+0^2+5^2=4+9+25=38$

c.

$(\Sigma x)^2=(2+3+0+5)^2=10^2=100$

d.

$\begin{gathered} SS=\Sigma(x-\bar{x})^2 \\ where: \\ \bar{x}=\frac{2+3+0+5}{4}=\frac{10}{4}=2.5 \\ so: \\ SS=(2-2.5)^2+(3-2.5)^2+(0-2.5)^2+(5-2.5)^2 \\ SS=(-0.5)^2+(0.5)^2+(-2.5)^2+(2.5)^2 \\ SS=13 \end{gathered}$