Alyssa is trying to decide where to spend this year's vacation. She could go snorkeling in the *Sea of Tranquility on the Moon or she could go skiing on *Mount Olympus on Mars. With the price of fuel, she is wondering how much she will save by traveling to the Moon instead of Mars. Round trip to Mars ( ) is km, but round trip to the Moon ( ) is only km. Her car gets km/L of fuel. At a cost of per liter of fuel, how much will she save by going snorkeling instead of skiing? Convert and to scientific notation before listing them in the Given. *(Note to student: We fully realize that there is no water in the Sea of Tranquility and there is no snow on Mount Olympus. We also realize that no car getskm/L of fuel and that you cannot drive to either Mars or the Moon. However, by the time you read this, fuel might costper liter!)
First convert each distance to scientific notation:

Given: =

km =

km

fuel rate =

km/L

cost of fuel =

dollars/L

Find: difference in fuel consumption and fuel cost
Next, divide each distance measurement by km/L to get the number of liters of fuel needed for the trip to Mars,

() and for the trip to the Moon ( ):

=

L =

L

Now find the cost of fuel for the trip to Mars ( ) and for the trip to the Moon ( ):

= $

= $

Next subtract the difference between the two costs: (Hint: Before subtracting, you must convert one of the measurements so they both have the same power of ten.) Be sure to convert your final answer into standard form.

Amount saved by going to the Moon instead of Mars: $