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Calculation related to 3 quantities.


zak100

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Hi,

I am trying to solve the following:
A person shovels driveways to earn money. She can shovel 12 driveways in 6 hours. She earns 18$ for each driveway.The person needs 360$ to buy a computer. How may hours does the person need to work?

I am using unity method :
18$----6 hour
1 $----6/18
360$.....6/18 * 360
= 120 hours

Some body please guide me.

Zulfi.

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4 minutes ago, zak100 said:

She can shovel 12 driveways in 6 hours. She earns 18$ for each driveway

Hint: Start by checking if the conclusion believe matches the above condition

5 minutes ago, zak100 said:

18$----6 hour

 

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Hi,

Thanks.

 

There is only one value for driveway i.e. 12. There are 2 values for earnings. Two values for hour, one is 360$ and the other is unknown. I can't figure out the other value for drive way.

 

Somebody please guide me.

 

Zulfi. 

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4 minutes ago, zak100 said:

There is only one value for driveway i.e. 12.

That is the number of driveways in 6 hours. So, how long for one driveway?

5 minutes ago, zak100 said:

There are 2 values for earnings.

Only one that I can see: $18 / driveway. 

Combine that with the previous answer (time per driveway) to work out how much she earns per hour. 

7 minutes ago, zak100 said:

Two values for hour, one is 360$ and the other is unknown.

That is not the value for an hour, that is the total she needs to earn. 

Use that and the previous answer (how much she earns per hour) to calculate how many hours she has to work. 

!

Moderator Note

Moved to Homework Help, as that seems more appropriate 

 
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3 hours ago, zak100 said:


A person shovels driveways to earn money. She can shovel 12 driveways in 6 hours. She earns 18$ for each driveway.The person needs 360$ to buy a computer. How may hours does the person need to work?

Reverse maths going from the end of this sentence to the beginning. i.e. 360$ is needed. Each driveway gives $18. How many driveways is needed? Then continue with the rest paying attention to units/dimensions.. "driveway" can be considered as unit/dimension as well.

Did you have "cancelling units"/"dimensional analysis"/"unit analysis" on physics or eventually on chemistry lessons?

https://www.google.com/search?q=cancel+of+units

 

Edited by Sensei
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