SOLUTION: My average electricity bill for the months of November, December, January, and February was $200. The highest month was January which was twice February. December was $10 less than

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Question 104086: My average electricity bill for the months of November, December, January, and February was $200. The highest month was January which was twice February. December was $10 less than January and November was $24 less than February. How much was my bill in each of the months November, December, January, and February?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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My average electricity bill for the months of November, December, January, and February was $200. The highest month was January which was twice February. December was $10 less than January and November was $24 less than February. How much was my bill in each of the months November, December, January, and February?
:
%28N+%2B+D+%2B+J+%2B+F%29%2F4 = 200
:
Write equations for each statement:
:
"January which was twice February."
J = 2F
or
F = .5J
:
"December was $10 less than January"
D = J - 10
:
"November was $24 less than February."
N = F - 24
We want to get everything in terms of J, substitute .5J for F:
N = .5J - 24
:
Substitute and you have;
%28%28.5J-24%29+%2B+%28J-10%29+%2B+J+%2B+.5J%29%2F4 = 200
:
Mult by 4 to get rid of the denominators, remove the brackets:
.5J - 24 + J - 10 + J + .5J = 800
:
.5J + J + J + .5J - 24 - 10 = 800; group like terms and do the math
3J - 34 = 800
3J = 800 + 34
J = 834/3
J = $278
Then
F = 278/2 = $139
and
N = 139 - 24 = $115
and
D = 278 - 10 = $268
:
:
Check on a calc:
%28115+%2B+268+%2B+278+%2B+139%29%2F4 = 200