Margie's car can go 32 miles on a gallon of gas, and the gas costs 4 per gallon. How many miles can margie drive on $20 worth of gas

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First, list out the points we have to solve.

1. For $4 she gets 1 gallon of gas, then for $20 how many gallons of gas can she get?

2. With 1 gallon of gas she can travel 32 miles, then how many miles can she travel with the gas...

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First, list out the points we have to solve.

1. For $4 she gets 1 gallon of gas, then for $20 how many gallons of gas can she get?

2. With 1 gallon of gas she can travel 32 miles, then how many miles can she travel with the gas worth of $20?

Now lets solve 

1.       $4           - 1 gallon

          $20         - `x` gallons

by cross-multiplication we get, `4x = 20`

 

`=gt x = 20/4 = 5 gallons `

2.       1 gallon     - 32 miles

          5 gallons    - `y` miles

again by cross-multiplication, we get `1y = 32 X 5 = 160miles`

 

`therefore` she can travel 160 miles with the gas worth $20.

 

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For this type of word problem, the given conditions can act as conversion factor or ratio.

 Let us list the given conditions:

Condition 1: 32 miles on a gallon of gas.

As conversion factor:  32 miles = 1 gallon gas

              32 miles               1 gallon gas

As ratio:  ---------------  or  ----------------------

              1 gallon gas            32 miles

 

Condition 2: Gas costs 4 per gallon of gas.

As conversion factor:  $ 4 = 1 gallon gas

              $ 4                       1 gallon gas

As ratio:  ---------------  or  ----------------------

              1 gallon gas              $ 4 

 

 Given:  $20 worth of gas.

 We can use conversion table to convert $20 = ? miles

 using the given conversion factor or ratios. The units will serve as a guide

 on how the conversion factors/ratios will be plug-in the table.

 

 In the conversion table, same units should be on the opposite sides to cancel out.

 

$20   |   1 gallon gas    |    32 miles   |

        |---------------------| ---------------|   = 160 miles.

        |      $ 4               | 1 gallon gas|

 

Note: The $ and gallon gas units can be cancelled out and we will be left with the unit of "miles".

 

Answer:  Margie can drive her car a distance of 160 miles to consume the $20 worth of gas.

 

 

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First, let's summarize what we know.

  • Gas costs $4 per gallon.
  • Margie's gas mileage is 32 miles per gallon.
  • Margie bought $20 dollars of gas.

There are two sub-steps to answer this question. First, we must calculate how many gallons of gas Margie purchased for #20. Then we can calculate how many miles Margie can drive.

For the first part, we divide the amount spent by the price of gas to find the amount of gas purchased.

20 dollars / 4 dollars per gallon = 5 gallons of gas.

Now, we can simply multiply Margie's gas mileage by the amount of gas in her tank.

32 miles per gallon x 5 gallons = 160 miles.

Thus, Margie can drive 160 miles on five gallons ($20 dollars worth) of gas. 

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