SOLUTION: The price of gas at your local convenience store is $3.51 on Monday. On Wednesday, the price has decreased by 22%. On Friday, the price has increased by 14% from where it was on We

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: The price of gas at your local convenience store is $3.51 on Monday. On Wednesday, the price has decreased by 22%. On Friday, the price has increased by 14% from where it was on We      Log On


   

Question 735197: The price of gas at your local convenience store is $3.51 on Monday. On Wednesday, the price has decreased by 22%. On Friday, the price has increased by 14% from where it was on Wednesday. How much would it cost to fill up an 11 gallon fuel tank? Express your answer to the nearest penny.
Answer by GratefulGeek(3) About Me  (Show Source):
You can put this solution on YOUR website!
What we know: Gas Price on Monday $3.51, 22% decrease on Wednesday from Monday price, 14% increase on Friday from Wednesday price.
What we want: Cost to fill 11 gallon tank on Friday
(1) Calculate 22% of Mondays price:
.22%2A3.51+=+.77
NOTE: this is the price decrease from Monday to Wednesday $0.77
(2) Subtract this figure from Monday's price:
3.51-0.77+=+2.74
NOTE: This is the price on Wednesday $2.74
(3) Calculate 14% of Wednesday's price:
.14%2A2.74+=+.38
NOTE: this is the price increase from Wednesday to Friday $0.38
(4) Add this figure to Wednesday's price:
2.74+%2B+0.38+=+3.12
Note this is Friday's price $3.12
(5) Calculate the cost of filling your 11 gallon tank:
3.12%2A11+=+34.32
Thus it will cost $34.32 to fill an 11 gallon tank on Friday at this particular convenient store.
Likewise, if we filled up on Wednesday it would cost us $30.14 and on Monday it would cost $38.61