Why Is the Value '2' Used in Calculating Coin Variance?

[werson9339]

Homework Statement

A bag contains a large number of coins comprises of 1 cent and 5 cents coins in the ration of 1:3

find the man and variance of the values of coins..
i have attached the sample ans here. i don't understand why the value of '2' is used?? why not '5' ...for me '5' represent 5 cents.

Homework Equations

The Attempt at a Solution

 

[Mark44]

Homework Statement

A bag contains a large number of coins comprises of 1 cent and 5 cents coins in the ration of 1:3

find the man and variance of the values of coins..
i have attached the sample ans here. i don't understand why the value of '2' is used?? why not '5' ...for me '5' represent 5 cents.

Homework Equations

The Attempt at a Solution

I think there is a typo in the sample answer. The mean should be 1*1/4 + 5*3/4 = 1/4 + 15/14 = 16/4 = 4 (cents).