Put in terms of a
b=2a
a=a
c=a-15000
2a+a+a-15000=109000
2a+a+a=124000
4a=124000
a=31000
Candidate B received 62000 votes
Well you find how much the error was and divide it by the amount he predicted.
30/230= 0.13 0.13=13%
The class midpoint is the lower class limit plus the upper class limit divided by 2 . Add the midpoints column to the original table.
