ShmoopTube

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Thank you We sneak And here's your shmoop du jour

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Brought to you by public transportation You may bring a

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sandwich with you onto the subway but you're definitely not

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goingto eat fresh All right Chavan is starting a new

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job and wants to minimize her commuting costs She has

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two options for communiqu drive or take the train Her

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car's fuel economy is thirty two miles a gallon Job

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is located 20 miles from the house And parking at

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work cost two Fifty a day Javan could also take

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public transportation and get to work She drive two point

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five miles to the train station and pay three seventy

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five each way from train barking its train station is

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free Which of the following statements is true and hear

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the pencil answers All right Really compared gas here Train

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car All right well to drive or not to drive

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That is the question here for us this really is

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a no brainer Have you ever heard of anyone having

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a bad case of the train rage But okay Sounds

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like sherman is more concerned about the money aspect of

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things and well we can respect that her driving costs

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would be made up Of two factors the cost of

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gas and the cost of parking Parking is two Fifty

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a day Easy enough We're told that her jobs twenty

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miles from her house assuming she's actually gonna be driving

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back home each day and not passing out on a

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cot in the break room That's forty miles of driving

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each day she gets thirty two miles a gallon so

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let's see how much he's gassing it up Well fortified

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by thirty two is one point two five so she's

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using one and a quarter gallons for each round trip

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to and from the office We can write this now

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is an equation The expression one point two five x

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plus two point five or x is the price of

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gas All right we'll let that idol remain there now

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onto the train option there's still five miles of driving

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involved two point five miles to the train station and

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two point five miles back which will use up five

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thirty seconds of a gallon of gas Want that in

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a decimals form so it lines up with our previous

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expression for driving We take five divided by thirty two

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and we get point One five six to five Well

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the train cost three seventy five each way or seven

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Fifty total each day So the expression for the train

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will be point one five sixty five x plus seven

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point five we'd like to know when the cost of

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each would be the same So let's set these two

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equal to one another and just solve for x That

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gives us one point two five x plus two point

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five equals point one five sixty five x plus seven

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point five we can start by subtracting two point five

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from both sides to get one point Two five Acts

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evil point 1:5 60 five x plus five then subtract point

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one five six to five x from each side and

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we wind up with one point o nine three seven

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five x equals five don't by both sides by one

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point nine three seven five and it looks like axe

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comes out to win right around four point five seven

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and would you look at that option d suggest that

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if gas is more than four fifty seven a gallon

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is cheaper to take the train we can double check

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our work by plugging in a few values for acts

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above and below the forfeit seven mark we'll see that

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Yeah it totally checks out Well these are answer and

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she even got the answer She was looking for an

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even better She found something to do during her commute

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to make the sun go buy a shame She's not 00:03:14.25 --> [endTime] big on crossword puzzle

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